drivers/mtd/nand/raw/nandsim.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * NAND flash simulator.
   4  *
   5  * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org>
   6  *
   7  * Copyright (C) 2004 Nokia Corporation
   8  *
   9  * Note: NS means "NAND Simulator".
  10  * Note: Input means input TO flash chip, output means output FROM chip.
  11  */
  12
  13 #define pr_fmt(fmt)  "[nandsim]" fmt
  14
  15 #include <linux/init.h>
  16 #include <linux/types.h>
  17 #include <linux/module.h>
  18 #include <linux/moduleparam.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/math64.h>
  21 #include <linux/slab.h>
  22 #include <linux/errno.h>
  23 #include <linux/string.h>
  24 #include <linux/mtd/mtd.h>
  25 #include <linux/mtd/rawnand.h>
  26 #include <linux/mtd/partitions.h>
  27 #include <linux/delay.h>
  28 #include <linux/list.h>
  29 #include <linux/random.h>
  30 #include <linux/sched.h>
  31 #include <linux/sched/mm.h>
  32 #include <linux/fs.h>
  33 #include <linux/pagemap.h>
  34 #include <linux/seq_file.h>
  35 #include <linux/debugfs.h>
  36
  37 /* Default simulator parameters values */
  38 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
  39     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
  40     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
  41     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
  42 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
  43 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
  44 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
  45 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
  46 #endif
  47
  48 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
  49 #define CONFIG_NANDSIM_ACCESS_DELAY 25
  50 #endif
  51 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
  52 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
  53 #endif
  54 #ifndef CONFIG_NANDSIM_ERASE_DELAY
  55 #define CONFIG_NANDSIM_ERASE_DELAY 2
  56 #endif
  57 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
  58 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
  59 #endif
  60 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
  61 #define CONFIG_NANDSIM_INPUT_CYCLE  50
  62 #endif
  63 #ifndef CONFIG_NANDSIM_BUS_WIDTH
  64 #define CONFIG_NANDSIM_BUS_WIDTH  8
  65 #endif
  66 #ifndef CONFIG_NANDSIM_DO_DELAYS
  67 #define CONFIG_NANDSIM_DO_DELAYS  0
  68 #endif
  69 #ifndef CONFIG_NANDSIM_LOG
  70 #define CONFIG_NANDSIM_LOG        0
  71 #endif
  72 #ifndef CONFIG_NANDSIM_DBG
  73 #define CONFIG_NANDSIM_DBG        0
  74 #endif
  75 #ifndef CONFIG_NANDSIM_MAX_PARTS
  76 #define CONFIG_NANDSIM_MAX_PARTS  32
  77 #endif
  78
  79 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
  80 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
  81 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
  82 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
  83 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
  84 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
  85 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
  86 static uint log            = CONFIG_NANDSIM_LOG;
  87 static uint dbg            = CONFIG_NANDSIM_DBG;
  88 static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];
  89 static unsigned int parts_num;
  90 static char *badblocks = NULL;
  91 static char *weakblocks = NULL;
  92 static char *weakpages = NULL;
  93 static unsigned int bitflips = 0;
  94 static char *gravepages = NULL;
  95 static unsigned int overridesize = 0;
  96 static char *cache_file = NULL;
  97 static unsigned int bbt;
  98 static unsigned int bch;
  99 static u_char id_bytes[8] = {
 100         [0] = CONFIG_NANDSIM_FIRST_ID_BYTE,
 101         [1] = CONFIG_NANDSIM_SECOND_ID_BYTE,
 102         [2] = CONFIG_NANDSIM_THIRD_ID_BYTE,
 103         [3] = CONFIG_NANDSIM_FOURTH_ID_BYTE,
 104         [4 ... 7] = 0xFF,
 105 };
 106
 107 module_param_array(id_bytes, byte, NULL, 0400);
 108 module_param_named(first_id_byte, id_bytes[0], byte, 0400);
 109 module_param_named(second_id_byte, id_bytes[1], byte, 0400);
 110 module_param_named(third_id_byte, id_bytes[2], byte, 0400);
 111 module_param_named(fourth_id_byte, id_bytes[3], byte, 0400);
 112 module_param(access_delay,   uint, 0400);
 113 module_param(programm_delay, uint, 0400);
 114 module_param(erase_delay,    uint, 0400);
 115 module_param(output_cycle,   uint, 0400);
 116 module_param(input_cycle,    uint, 0400);
 117 module_param(bus_width,      uint, 0400);
 118 module_param(do_delays,      uint, 0400);
 119 module_param(log,            uint, 0400);
 120 module_param(dbg,            uint, 0400);
 121 module_param_array(parts, ulong, &parts_num, 0400);
 122 module_param(badblocks,      charp, 0400);
 123 module_param(weakblocks,     charp, 0400);
 124 module_param(weakpages,      charp, 0400);
 125 module_param(bitflips,       uint, 0400);
 126 module_param(gravepages,     charp, 0400);
 127 module_param(overridesize,   uint, 0400);
 128 module_param(cache_file,     charp, 0400);
 129 module_param(bbt,            uint, 0400);
 130 module_param(bch,            uint, 0400);
 131
 132 MODULE_PARM_DESC(id_bytes,       "The ID bytes returned by NAND Flash 'read ID' command");
 133 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID) (obsolete)");
 134 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID) (obsolete)");
 135 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command (obsolete)");
 136 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command (obsolete)");
 137 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");
 138 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
 139 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
 140 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");
 141 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");
 142 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
 143 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
 144 MODULE_PARM_DESC(log,            "Perform logging if not zero");
 145 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
 146 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
 147 /* Page and erase block positions for the following parameters are independent of any partitions */
 148 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
 149 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
 150                                  " separated by commas e.g. 113:2 means eb 113"
 151                                  " can be erased only twice before failing");
 152 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
 153                                  " separated by commas e.g. 1401:2 means page 1401"
 154                                  " can be written only twice before failing");
 155 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
 156 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
 157                                  " separated by commas e.g. 1401:2 means page 1401"
 158                                  " can be read only twice before failing");
 159 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
 160                                  "The size is specified in erase blocks and as the exponent of a power of two"
 161                                  " e.g. 5 means a size of 32 erase blocks");
 162 MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");
 163 MODULE_PARM_DESC(bbt,            "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");
 164 MODULE_PARM_DESC(bch,            "Enable BCH ecc and set how many bits should "
 165                                  "be correctable in 512-byte blocks");
 166
 167 /* The largest possible page size */
 168 #define NS_LARGEST_PAGE_SIZE    4096
 169
 170 /* Simulator's output macros (logging, debugging, warning, error) */
 171 #define NS_LOG(args...) \
 172         do { if (log) pr_debug(" log: " args); } while(0)
 173 #define NS_DBG(args...) \
 174         do { if (dbg) pr_debug(" debug: " args); } while(0)
 175 #define NS_WARN(args...) \
 176         do { pr_warn(" warning: " args); } while(0)
 177 #define NS_ERR(args...) \
 178         do { pr_err(" error: " args); } while(0)
 179 #define NS_INFO(args...) \
 180         do { pr_info(" " args); } while(0)
 181
 182 /* Busy-wait delay macros (microseconds, milliseconds) */
 183 #define NS_UDELAY(us) \
 184         do { if (do_delays) udelay(us); } while(0)
 185 #define NS_MDELAY(us) \
 186         do { if (do_delays) mdelay(us); } while(0)
 187
 188 /* Is the nandsim structure initialized ? */
 189 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
 190
 191 /* Good operation completion status */
 192 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
 193
 194 /* Operation failed completion status */
 195 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
 196
 197 /* Calculate the page offset in flash RAM image by (row, column) address */
 198 #define NS_RAW_OFFSET(ns) \
 199         (((ns)->regs.row * (ns)->geom.pgszoob) + (ns)->regs.column)
 200
 201 /* Calculate the OOB offset in flash RAM image by (row, column) address */
 202 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
 203
 204 /* Calculate the byte shift in the next page to access */
 205 #define NS_PAGE_BYTE_SHIFT(ns) ((ns)->regs.column + (ns)->regs.off)
 206
 207 /* After a command is input, the simulator goes to one of the following states */
 208 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
 209 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
 210 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
 211 #define STATE_CMD_PAGEPROG     0x00000004 /* start page program */
 212 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
 213 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
 214 #define STATE_CMD_STATUS       0x00000007 /* read status */
 215 #define STATE_CMD_SEQIN        0x00000009 /* sequential data input */
 216 #define STATE_CMD_READID       0x0000000A /* read ID */
 217 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
 218 #define STATE_CMD_RESET        0x0000000C /* reset */
 219 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
 220 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
 221 #define STATE_CMD_MASK         0x0000000F /* command states mask */
 222
 223 /* After an address is input, the simulator goes to one of these states */
 224 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
 225 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
 226 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
 227 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
 228 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
 229
 230 /* During data input/output the simulator is in these states */
 231 #define STATE_DATAIN           0x00000100 /* waiting for data input */
 232 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
 233
 234 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
 235 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
 236 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
 237 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
 238
 239 /* Previous operation is done, ready to accept new requests */
 240 #define STATE_READY            0x00000000
 241
 242 /* This state is used to mark that the next state isn't known yet */
 243 #define STATE_UNKNOWN          0x10000000
 244
 245 /* Simulator's actions bit masks */
 246 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
 247 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
 248 #define ACTION_SECERASE  0x00300000 /* erase sector */
 249 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
 250 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
 251 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
 252 #define ACTION_MASK      0x00700000 /* action mask */
 253
 254 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
 255 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
 256
 257 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
 258 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
 259 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
 260 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
 261 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
 262 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
 263 #define OPT_SMALLPAGE    (OPT_PAGE512) /* 512-byte page chips */
 264
 265 /* Remove action bits from state */
 266 #define NS_STATE(x) ((x) & ~ACTION_MASK)
 267
 268 /*
 269  * Maximum previous states which need to be saved. Currently saving is
 270  * only needed for page program operation with preceded read command
 271  * (which is only valid for 512-byte pages).
 272  */
 273 #define NS_MAX_PREVSTATES 1
 274
 275 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
 276 #define NS_MAX_HELD_PAGES 16
 277
 278 /*
 279  * A union to represent flash memory contents and flash buffer.
 280  */
 281 union ns_mem {
 282         u_char *byte;    /* for byte access */
 283         uint16_t *word;  /* for 16-bit word access */
 284 };
 285
 286 /*
 287  * The structure which describes all the internal simulator data.
 288  */
 289 struct nandsim {
 290         struct nand_chip chip;
 291         struct nand_controller base;
 292         struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
 293         unsigned int nbparts;
 294
 295         uint busw;              /* flash chip bus width (8 or 16) */
 296         u_char ids[8];          /* chip's ID bytes */
 297         uint32_t options;       /* chip's characteristic bits */
 298         uint32_t state;         /* current chip state */
 299         uint32_t nxstate;       /* next expected state */
 300
 301         uint32_t *op;           /* current operation, NULL operations isn't known yet  */
 302         uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
 303         uint16_t npstates;      /* number of previous states saved */
 304         uint16_t stateidx;      /* current state index */
 305
 306         /* The simulated NAND flash pages array */
 307         union ns_mem *pages;
 308
 309         /* Slab allocator for nand pages */
 310         struct kmem_cache *nand_pages_slab;
 311
 312         /* Internal buffer of page + OOB size bytes */
 313         union ns_mem buf;
 314
 315         /* NAND flash "geometry" */
 316         struct {
 317                 uint64_t totsz;     /* total flash size, bytes */
 318                 uint32_t secsz;     /* flash sector (erase block) size, bytes */
 319                 uint pgsz;          /* NAND flash page size, bytes */
 320                 uint oobsz;         /* page OOB area size, bytes */
 321                 uint64_t totszoob;  /* total flash size including OOB, bytes */
 322                 uint pgszoob;       /* page size including OOB , bytes*/
 323                 uint secszoob;      /* sector size including OOB, bytes */
 324                 uint pgnum;         /* total number of pages */
 325                 uint pgsec;         /* number of pages per sector */
 326                 uint secshift;      /* bits number in sector size */
 327                 uint pgshift;       /* bits number in page size */
 328                 uint pgaddrbytes;   /* bytes per page address */
 329                 uint secaddrbytes;  /* bytes per sector address */
 330                 uint idbytes;       /* the number ID bytes that this chip outputs */
 331         } geom;
 332
 333         /* NAND flash internal registers */
 334         struct {
 335                 unsigned command; /* the command register */
 336                 u_char   status;  /* the status register */
 337                 uint     row;     /* the page number */
 338                 uint     column;  /* the offset within page */
 339                 uint     count;   /* internal counter */
 340                 uint     num;     /* number of bytes which must be processed */
 341                 uint     off;     /* fixed page offset */
 342         } regs;
 343
 344         /* NAND flash lines state */
 345         struct {
 346                 int ce;  /* chip Enable */
 347                 int cle; /* command Latch Enable */
 348                 int ale; /* address Latch Enable */
 349                 int wp;  /* write Protect */
 350         } lines;
 351
 352         /* Fields needed when using a cache file */
 353         struct file *cfile; /* Open file */
 354         unsigned long *pages_written; /* Which pages have been written */
 355         void *file_buf;
 356         struct page *held_pages[NS_MAX_HELD_PAGES];
 357         int held_cnt;
 358
 359         /* debugfs entry */
 360         struct dentry *dent;
 361 };
 362
 363 /*
 364  * Operations array. To perform any operation the simulator must pass
 365  * through the correspondent states chain.
 366  */
 367 static struct nandsim_operations {
 368         uint32_t reqopts;  /* options which are required to perform the operation */
 369         uint32_t states[NS_OPER_STATES]; /* operation's states */
 370 } ops[NS_OPER_NUM] = {
 371         /* Read page + OOB from the beginning */
 372         {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
 373                         STATE_DATAOUT, STATE_READY}},
 374         /* Read page + OOB from the second half */
 375         {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
 376                         STATE_DATAOUT, STATE_READY}},
 377         /* Read OOB */
 378         {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
 379                         STATE_DATAOUT, STATE_READY}},
 380         /* Program page starting from the beginning */
 381         {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
 382                         STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 383         /* Program page starting from the beginning */
 384         {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
 385                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 386         /* Program page starting from the second half */
 387         {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
 388                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 389         /* Program OOB */
 390         {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
 391                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 392         /* Erase sector */
 393         {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
 394         /* Read status */
 395         {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
 396         /* Read ID */
 397         {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
 398         /* Large page devices read page */
 399         {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
 400                                STATE_DATAOUT, STATE_READY}},
 401         /* Large page devices random page read */
 402         {OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
 403                                STATE_DATAOUT, STATE_READY}},
 404 };
 405
 406 struct weak_block {
 407         struct list_head list;
 408         unsigned int erase_block_no;
 409         unsigned int max_erases;
 410         unsigned int erases_done;
 411 };
 412
 413 static LIST_HEAD(weak_blocks);
 414
 415 struct weak_page {
 416         struct list_head list;
 417         unsigned int page_no;
 418         unsigned int max_writes;
 419         unsigned int writes_done;
 420 };
 421
 422 static LIST_HEAD(weak_pages);
 423
 424 struct grave_page {
 425         struct list_head list;
 426         unsigned int page_no;
 427         unsigned int max_reads;
 428         unsigned int reads_done;
 429 };
 430
 431 static LIST_HEAD(grave_pages);
 432
 433 static unsigned long *erase_block_wear = NULL;
 434 static unsigned int wear_eb_count = 0;
 435 static unsigned long total_wear = 0;
 436
 437 /* MTD structure for NAND controller */
 438 static struct mtd_info *nsmtd;
 439
 440 static int ns_show(struct seq_file *m, void *private)
 441 {
 442         unsigned long wmin = -1, wmax = 0, avg;
 443         unsigned long deciles[10], decile_max[10], tot = 0;
 444         unsigned int i;
 445
 446         /* Calc wear stats */
 447         for (i = 0; i < wear_eb_count; ++i) {
 448                 unsigned long wear = erase_block_wear[i];
 449                 if (wear < wmin)
 450                         wmin = wear;
 451                 if (wear > wmax)
 452                         wmax = wear;
 453                 tot += wear;
 454         }
 455
 456         for (i = 0; i < 9; ++i) {
 457                 deciles[i] = 0;
 458                 decile_max[i] = (wmax * (i + 1) + 5) / 10;
 459         }
 460         deciles[9] = 0;
 461         decile_max[9] = wmax;
 462         for (i = 0; i < wear_eb_count; ++i) {
 463                 int d;
 464                 unsigned long wear = erase_block_wear[i];
 465                 for (d = 0; d < 10; ++d)
 466                         if (wear <= decile_max[d]) {
 467                                 deciles[d] += 1;
 468                                 break;
 469                         }
 470         }
 471         avg = tot / wear_eb_count;
 472
 473         /* Output wear report */
 474         seq_printf(m, "Total numbers of erases:  %lu\n", tot);
 475         seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);
 476         seq_printf(m, "Average number of erases: %lu\n", avg);
 477         seq_printf(m, "Maximum number of erases: %lu\n", wmax);
 478         seq_printf(m, "Minimum number of erases: %lu\n", wmin);
 479         for (i = 0; i < 10; ++i) {
 480                 unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
 481                 if (from > decile_max[i])
 482                         continue;
 483                 seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
 484                         from,
 485                         decile_max[i],
 486                         deciles[i]);
 487         }
 488
 489         return 0;
 490 }
 491 DEFINE_SHOW_ATTRIBUTE(ns);
 492
 493 /**
 494  * ns_debugfs_create - initialize debugfs
 495  * @ns: nandsim device description object
 496  *
 497  * This function creates all debugfs files for UBI device @ubi. Returns zero in
 498  * case of success and a negative error code in case of failure.
 499  */
 500 static int ns_debugfs_create(struct nandsim *ns)
 501 {
 502         struct dentry *root = nsmtd->dbg.dfs_dir;
 503
 504         /*
 505          * Just skip debugfs initialization when the debugfs directory is
 506          * missing.
 507          */
 508         if (IS_ERR_OR_NULL(root)) {
 509                 if (IS_ENABLED(CONFIG_DEBUG_FS) &&
 510                     !IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
 511                         NS_WARN("CONFIG_MTD_PARTITIONED_MASTER must be enabled to expose debugfs stuff\n");
 512                 return 0;
 513         }
 514
 515         ns->dent = debugfs_create_file("nandsim_wear_report", 0400, root, ns,
 516                                        &ns_fops);
 517         if (IS_ERR_OR_NULL(ns->dent)) {
 518                 NS_ERR("cannot create \"nandsim_wear_report\" debugfs entry\n");
 519                 return -1;
 520         }
 521
 522         return 0;
 523 }
 524
 525 static void ns_debugfs_remove(struct nandsim *ns)
 526 {
 527         debugfs_remove_recursive(ns->dent);
 528 }
 529
 530 /*
 531  * Allocate array of page pointers, create slab allocation for an array
 532  * and initialize the array by NULL pointers.
 533  *
 534  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
 535  */
 536 static int __init ns_alloc_device(struct nandsim *ns)
 537 {
 538         struct file *cfile;
 539         int i, err;
 540
 541         if (cache_file) {
 542                 cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
 543                 if (IS_ERR(cfile))
 544                         return PTR_ERR(cfile);
 545                 if (!(cfile->f_mode & FMODE_CAN_READ)) {
 546                         NS_ERR("alloc_device: cache file not readable\n");
 547                         err = -EINVAL;
 548                         goto err_close_filp;
 549                 }
 550                 if (!(cfile->f_mode & FMODE_CAN_WRITE)) {
 551                         NS_ERR("alloc_device: cache file not writeable\n");
 552                         err = -EINVAL;
 553                         goto err_close_filp;
 554                 }
 555                 ns->pages_written =
 556                         vzalloc(array_size(sizeof(unsigned long),
 557                                            BITS_TO_LONGS(ns->geom.pgnum)));
 558                 if (!ns->pages_written) {
 559                         NS_ERR("alloc_device: unable to allocate pages written array\n");
 560                         err = -ENOMEM;
 561                         goto err_close_filp;
 562                 }
 563                 ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 564                 if (!ns->file_buf) {
 565                         NS_ERR("alloc_device: unable to allocate file buf\n");
 566                         err = -ENOMEM;
 567                         goto err_free_pw;
 568                 }
 569                 ns->cfile = cfile;
 570
 571                 return 0;
 572
 573 err_free_pw:
 574                 vfree(ns->pages_written);
 575 err_close_filp:
 576                 filp_close(cfile, NULL);
 577
 578                 return err;
 579         }
 580
 581         ns->pages = vmalloc(array_size(sizeof(union ns_mem), ns->geom.pgnum));
 582         if (!ns->pages) {
 583                 NS_ERR("alloc_device: unable to allocate page array\n");
 584                 return -ENOMEM;
 585         }
 586         for (i = 0; i < ns->geom.pgnum; i++) {
 587                 ns->pages[i].byte = NULL;
 588         }
 589         ns->nand_pages_slab = kmem_cache_create("nandsim",
 590                                                 ns->geom.pgszoob, 0, 0, NULL);
 591         if (!ns->nand_pages_slab) {
 592                 NS_ERR("cache_create: unable to create kmem_cache\n");
 593                 err = -ENOMEM;
 594                 goto err_free_pg;
 595         }
 596
 597         return 0;
 598
 599 err_free_pg:
 600         vfree(ns->pages);
 601
 602         return err;
 603 }
 604
 605 /*
 606  * Free any allocated pages, and free the array of page pointers.
 607  */
 608 static void ns_free_device(struct nandsim *ns)
 609 {
 610         int i;
 611
 612         if (ns->cfile) {
 613                 kfree(ns->file_buf);
 614                 vfree(ns->pages_written);
 615                 filp_close(ns->cfile, NULL);
 616                 return;
 617         }
 618
 619         if (ns->pages) {
 620                 for (i = 0; i < ns->geom.pgnum; i++) {
 621                         if (ns->pages[i].byte)
 622                                 kmem_cache_free(ns->nand_pages_slab,
 623                                                 ns->pages[i].byte);
 624                 }
 625                 kmem_cache_destroy(ns->nand_pages_slab);
 626                 vfree(ns->pages);
 627         }
 628 }
 629
 630 static char __init *ns_get_partition_name(int i)
 631 {
 632         return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i);
 633 }
 634
 635 /*
 636  * Initialize the nandsim structure.
 637  *
 638  * RETURNS: 0 if success, -ERRNO if failure.
 639  */
 640 static int __init ns_init(struct mtd_info *mtd)
 641 {
 642         struct nand_chip *chip = mtd_to_nand(mtd);
 643         struct nandsim   *ns   = nand_get_controller_data(chip);
 644         int i, ret = 0;
 645         uint64_t remains;
 646         uint64_t next_offset;
 647
 648         if (NS_IS_INITIALIZED(ns)) {
 649                 NS_ERR("init_nandsim: nandsim is already initialized\n");
 650                 return -EIO;
 651         }
 652
 653         /* Initialize the NAND flash parameters */
 654         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
 655         ns->geom.totsz    = mtd->size;
 656         ns->geom.pgsz     = mtd->writesize;
 657         ns->geom.oobsz    = mtd->oobsize;
 658         ns->geom.secsz    = mtd->erasesize;
 659         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
 660         ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
 661         ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
 662         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
 663         ns->geom.pgshift  = chip->page_shift;
 664         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
 665         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
 666         ns->options = 0;
 667
 668         if (ns->geom.pgsz == 512) {
 669                 ns->options |= OPT_PAGE512;
 670                 if (ns->busw == 8)
 671                         ns->options |= OPT_PAGE512_8BIT;
 672         } else if (ns->geom.pgsz == 2048) {
 673                 ns->options |= OPT_PAGE2048;
 674         } else if (ns->geom.pgsz == 4096) {
 675                 ns->options |= OPT_PAGE4096;
 676         } else {
 677                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
 678                 return -EIO;
 679         }
 680
 681         if (ns->options & OPT_SMALLPAGE) {
 682                 if (ns->geom.totsz <= (32 << 20)) {
 683                         ns->geom.pgaddrbytes  = 3;
 684                         ns->geom.secaddrbytes = 2;
 685                 } else {
 686                         ns->geom.pgaddrbytes  = 4;
 687                         ns->geom.secaddrbytes = 3;
 688                 }
 689         } else {
 690                 if (ns->geom.totsz <= (128 << 20)) {
 691                         ns->geom.pgaddrbytes  = 4;
 692                         ns->geom.secaddrbytes = 2;
 693                 } else {
 694                         ns->geom.pgaddrbytes  = 5;
 695                         ns->geom.secaddrbytes = 3;
 696                 }
 697         }
 698
 699         /* Fill the partition_info structure */
 700         if (parts_num > ARRAY_SIZE(ns->partitions)) {
 701                 NS_ERR("too many partitions.\n");
 702                 return -EINVAL;
 703         }
 704         remains = ns->geom.totsz;
 705         next_offset = 0;
 706         for (i = 0; i < parts_num; ++i) {
 707                 uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
 708
 709                 if (!part_sz || part_sz > remains) {
 710                         NS_ERR("bad partition size.\n");
 711                         return -EINVAL;
 712                 }
 713                 ns->partitions[i].name = ns_get_partition_name(i);
 714                 if (!ns->partitions[i].name) {
 715                         NS_ERR("unable to allocate memory.\n");
 716                         return -ENOMEM;
 717                 }
 718                 ns->partitions[i].offset = next_offset;
 719                 ns->partitions[i].size   = part_sz;
 720                 next_offset += ns->partitions[i].size;
 721                 remains -= ns->partitions[i].size;
 722         }
 723         ns->nbparts = parts_num;
 724         if (remains) {
 725                 if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
 726                         NS_ERR("too many partitions.\n");
 727                         ret = -EINVAL;
 728                         goto free_partition_names;
 729                 }
 730                 ns->partitions[i].name = ns_get_partition_name(i);
 731                 if (!ns->partitions[i].name) {
 732                         NS_ERR("unable to allocate memory.\n");
 733                         ret = -ENOMEM;
 734                         goto free_partition_names;
 735                 }
 736                 ns->partitions[i].offset = next_offset;
 737                 ns->partitions[i].size   = remains;
 738                 ns->nbparts += 1;
 739         }
 740
 741         if (ns->busw == 16)
 742                 NS_WARN("16-bit flashes support wasn't tested\n");
 743
 744         printk("flash size: %llu MiB\n",
 745                         (unsigned long long)ns->geom.totsz >> 20);
 746         printk("page size: %u bytes\n",         ns->geom.pgsz);
 747         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
 748         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
 749         printk("pages number: %u\n",            ns->geom.pgnum);
 750         printk("pages per sector: %u\n",        ns->geom.pgsec);
 751         printk("bus width: %u\n",               ns->busw);
 752         printk("bits in sector size: %u\n",     ns->geom.secshift);
 753         printk("bits in page size: %u\n",       ns->geom.pgshift);
 754         printk("bits in OOB size: %u\n",        ffs(ns->geom.oobsz) - 1);
 755         printk("flash size with OOB: %llu KiB\n",
 756                         (unsigned long long)ns->geom.totszoob >> 10);
 757         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
 758         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
 759         printk("options: %#x\n",                ns->options);
 760
 761         ret = ns_alloc_device(ns);
 762         if (ret)
 763                 goto free_partition_names;
 764
 765         /* Allocate / initialize the internal buffer */
 766         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 767         if (!ns->buf.byte) {
 768                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
 769                         ns->geom.pgszoob);
 770                 ret = -ENOMEM;
 771                 goto free_device;
 772         }
 773         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
 774
 775         return 0;
 776
 777 free_device:
 778         ns_free_device(ns);
 779 free_partition_names:
 780         for (i = 0; i < ARRAY_SIZE(ns->partitions); ++i)
 781                 kfree(ns->partitions[i].name);
 782
 783         return ret;
 784 }
 785
 786 /*
 787  * Free the nandsim structure.
 788  */
 789 static void ns_free(struct nandsim *ns)
 790 {
 791         int i;
 792
 793         for (i = 0; i < ARRAY_SIZE(ns->partitions); ++i)
 794                 kfree(ns->partitions[i].name);
 795
 796         kfree(ns->buf.byte);
 797         ns_free_device(ns);
 798
 799         return;
 800 }
 801
 802 static int ns_parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
 803 {
 804         char *w;
 805         int zero_ok;
 806         unsigned int erase_block_no;
 807         loff_t offset;
 808
 809         if (!badblocks)
 810                 return 0;
 811         w = badblocks;
 812         do {
 813                 zero_ok = (*w == '0' ? 1 : 0);
 814                 erase_block_no = simple_strtoul(w, &w, 0);
 815                 if (!zero_ok && !erase_block_no) {
 816                         NS_ERR("invalid badblocks.\n");
 817                         return -EINVAL;
 818                 }
 819                 offset = (loff_t)erase_block_no * ns->geom.secsz;
 820                 if (mtd_block_markbad(mtd, offset)) {
 821                         NS_ERR("invalid badblocks.\n");
 822                         return -EINVAL;
 823                 }
 824                 if (*w == ',')
 825                         w += 1;
 826         } while (*w);
 827         return 0;
 828 }
 829
 830 static int ns_parse_weakblocks(void)
 831 {
 832         char *w;
 833         int zero_ok;
 834         unsigned int erase_block_no;
 835         unsigned int max_erases;
 836         struct weak_block *wb;
 837
 838         if (!weakblocks)
 839                 return 0;
 840         w = weakblocks;
 841         do {
 842                 zero_ok = (*w == '0' ? 1 : 0);
 843                 erase_block_no = simple_strtoul(w, &w, 0);
 844                 if (!zero_ok && !erase_block_no) {
 845                         NS_ERR("invalid weakblocks.\n");
 846                         return -EINVAL;
 847                 }
 848                 max_erases = 3;
 849                 if (*w == ':') {
 850                         w += 1;
 851                         max_erases = simple_strtoul(w, &w, 0);
 852                 }
 853                 if (*w == ',')
 854                         w += 1;
 855                 wb = kzalloc(sizeof(*wb), GFP_KERNEL);
 856                 if (!wb) {
 857                         NS_ERR("unable to allocate memory.\n");
 858                         return -ENOMEM;
 859                 }
 860                 wb->erase_block_no = erase_block_no;
 861                 wb->max_erases = max_erases;
 862                 list_add(&wb->list, &weak_blocks);
 863         } while (*w);
 864         return 0;
 865 }
 866
 867 static int ns_erase_error(unsigned int erase_block_no)
 868 {
 869         struct weak_block *wb;
 870
 871         list_for_each_entry(wb, &weak_blocks, list)
 872                 if (wb->erase_block_no == erase_block_no) {
 873                         if (wb->erases_done >= wb->max_erases)
 874                                 return 1;
 875                         wb->erases_done += 1;
 876                         return 0;
 877                 }
 878         return 0;
 879 }
 880
 881 static int ns_parse_weakpages(void)
 882 {
 883         char *w;
 884         int zero_ok;
 885         unsigned int page_no;
 886         unsigned int max_writes;
 887         struct weak_page *wp;
 888
 889         if (!weakpages)
 890                 return 0;
 891         w = weakpages;
 892         do {
 893                 zero_ok = (*w == '0' ? 1 : 0);
 894                 page_no = simple_strtoul(w, &w, 0);
 895                 if (!zero_ok && !page_no) {
 896                         NS_ERR("invalid weakpages.\n");
 897                         return -EINVAL;
 898                 }
 899                 max_writes = 3;
 900                 if (*w == ':') {
 901                         w += 1;
 902                         max_writes = simple_strtoul(w, &w, 0);
 903                 }
 904                 if (*w == ',')
 905                         w += 1;
 906                 wp = kzalloc(sizeof(*wp), GFP_KERNEL);
 907                 if (!wp) {
 908                         NS_ERR("unable to allocate memory.\n");
 909                         return -ENOMEM;
 910                 }
 911                 wp->page_no = page_no;
 912                 wp->max_writes = max_writes;
 913                 list_add(&wp->list, &weak_pages);
 914         } while (*w);
 915         return 0;
 916 }
 917
 918 static int ns_write_error(unsigned int page_no)
 919 {
 920         struct weak_page *wp;
 921
 922         list_for_each_entry(wp, &weak_pages, list)
 923                 if (wp->page_no == page_no) {
 924                         if (wp->writes_done >= wp->max_writes)
 925                                 return 1;
 926                         wp->writes_done += 1;
 927                         return 0;
 928                 }
 929         return 0;
 930 }
 931
 932 static int ns_parse_gravepages(void)
 933 {
 934         char *g;
 935         int zero_ok;
 936         unsigned int page_no;
 937         unsigned int max_reads;
 938         struct grave_page *gp;
 939
 940         if (!gravepages)
 941                 return 0;
 942         g = gravepages;
 943         do {
 944                 zero_ok = (*g == '0' ? 1 : 0);
 945                 page_no = simple_strtoul(g, &g, 0);
 946                 if (!zero_ok && !page_no) {
 947                         NS_ERR("invalid gravepagess.\n");
 948                         return -EINVAL;
 949                 }
 950                 max_reads = 3;
 951                 if (*g == ':') {
 952                         g += 1;
 953                         max_reads = simple_strtoul(g, &g, 0);
 954                 }
 955                 if (*g == ',')
 956                         g += 1;
 957                 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 958                 if (!gp) {
 959                         NS_ERR("unable to allocate memory.\n");
 960                         return -ENOMEM;
 961                 }
 962                 gp->page_no = page_no;
 963                 gp->max_reads = max_reads;
 964                 list_add(&gp->list, &grave_pages);
 965         } while (*g);
 966         return 0;
 967 }
 968
 969 static int ns_read_error(unsigned int page_no)
 970 {
 971         struct grave_page *gp;
 972
 973         list_for_each_entry(gp, &grave_pages, list)
 974                 if (gp->page_no == page_no) {
 975                         if (gp->reads_done >= gp->max_reads)
 976                                 return 1;
 977                         gp->reads_done += 1;
 978                         return 0;
 979                 }
 980         return 0;
 981 }
 982
 983 static int ns_setup_wear_reporting(struct mtd_info *mtd)
 984 {
 985         wear_eb_count = div_u64(mtd->size, mtd->erasesize);
 986         erase_block_wear = kcalloc(wear_eb_count, sizeof(unsigned long), GFP_KERNEL);
 987         if (!erase_block_wear) {
 988                 NS_ERR("Too many erase blocks for wear reporting\n");
 989                 return -ENOMEM;
 990         }
 991         return 0;
 992 }
 993
 994 static void ns_update_wear(unsigned int erase_block_no)
 995 {
 996         if (!erase_block_wear)
 997                 return;
 998         total_wear += 1;
 999         /*
1000          * TODO: Notify this through a debugfs entry,
1001          * instead of showing an error message.
1002          */
1003         if (total_wear == 0)
1004                 NS_ERR("Erase counter total overflow\n");
1005         erase_block_wear[erase_block_no] += 1;
1006         if (erase_block_wear[erase_block_no] == 0)
1007                 NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1008 }
1009
1010 /*
1011  * Returns the string representation of 'state' state.
1012  */
1013 static char *ns_get_state_name(uint32_t state)
1014 {
1015         switch (NS_STATE(state)) {
1016                 case STATE_CMD_READ0:
1017                         return "STATE_CMD_READ0";
1018                 case STATE_CMD_READ1:
1019                         return "STATE_CMD_READ1";
1020                 case STATE_CMD_PAGEPROG:
1021                         return "STATE_CMD_PAGEPROG";
1022                 case STATE_CMD_READOOB:
1023                         return "STATE_CMD_READOOB";
1024                 case STATE_CMD_READSTART:
1025                         return "STATE_CMD_READSTART";
1026                 case STATE_CMD_ERASE1:
1027                         return "STATE_CMD_ERASE1";
1028                 case STATE_CMD_STATUS:
1029                         return "STATE_CMD_STATUS";
1030                 case STATE_CMD_SEQIN:
1031                         return "STATE_CMD_SEQIN";
1032                 case STATE_CMD_READID:
1033                         return "STATE_CMD_READID";
1034                 case STATE_CMD_ERASE2:
1035                         return "STATE_CMD_ERASE2";
1036                 case STATE_CMD_RESET:
1037                         return "STATE_CMD_RESET";
1038                 case STATE_CMD_RNDOUT:
1039                         return "STATE_CMD_RNDOUT";
1040                 case STATE_CMD_RNDOUTSTART:
1041                         return "STATE_CMD_RNDOUTSTART";
1042                 case STATE_ADDR_PAGE:
1043                         return "STATE_ADDR_PAGE";
1044                 case STATE_ADDR_SEC:
1045                         return "STATE_ADDR_SEC";
1046                 case STATE_ADDR_ZERO:
1047                         return "STATE_ADDR_ZERO";
1048                 case STATE_ADDR_COLUMN:
1049                         return "STATE_ADDR_COLUMN";
1050                 case STATE_DATAIN:
1051                         return "STATE_DATAIN";
1052                 case STATE_DATAOUT:
1053                         return "STATE_DATAOUT";
1054                 case STATE_DATAOUT_ID:
1055                         return "STATE_DATAOUT_ID";
1056                 case STATE_DATAOUT_STATUS:
1057                         return "STATE_DATAOUT_STATUS";
1058                 case STATE_READY:
1059                         return "STATE_READY";
1060                 case STATE_UNKNOWN:
1061                         return "STATE_UNKNOWN";
1062         }
1063
1064         NS_ERR("get_state_name: unknown state, BUG\n");
1065         return NULL;
1066 }
1067
1068 /*
1069  * Check if command is valid.
1070  *
1071  * RETURNS: 1 if wrong command, 0 if right.
1072  */
1073 static int ns_check_command(int cmd)
1074 {
1075         switch (cmd) {
1076
1077         case NAND_CMD_READ0:
1078         case NAND_CMD_READ1:
1079         case NAND_CMD_READSTART:
1080         case NAND_CMD_PAGEPROG:
1081         case NAND_CMD_READOOB:
1082         case NAND_CMD_ERASE1:
1083         case NAND_CMD_STATUS:
1084         case NAND_CMD_SEQIN:
1085         case NAND_CMD_READID:
1086         case NAND_CMD_ERASE2:
1087         case NAND_CMD_RESET:
1088         case NAND_CMD_RNDOUT:
1089         case NAND_CMD_RNDOUTSTART:
1090                 return 0;
1091
1092         default:
1093                 return 1;
1094         }
1095 }
1096
1097 /*
1098  * Returns state after command is accepted by command number.
1099  */
1100 static uint32_t ns_get_state_by_command(unsigned command)
1101 {
1102         switch (command) {
1103                 case NAND_CMD_READ0:
1104                         return STATE_CMD_READ0;
1105                 case NAND_CMD_READ1:
1106                         return STATE_CMD_READ1;
1107                 case NAND_CMD_PAGEPROG:
1108                         return STATE_CMD_PAGEPROG;
1109                 case NAND_CMD_READSTART:
1110                         return STATE_CMD_READSTART;
1111                 case NAND_CMD_READOOB:
1112                         return STATE_CMD_READOOB;
1113                 case NAND_CMD_ERASE1:
1114                         return STATE_CMD_ERASE1;
1115                 case NAND_CMD_STATUS:
1116                         return STATE_CMD_STATUS;
1117                 case NAND_CMD_SEQIN:
1118                         return STATE_CMD_SEQIN;
1119                 case NAND_CMD_READID:
1120                         return STATE_CMD_READID;
1121                 case NAND_CMD_ERASE2:
1122                         return STATE_CMD_ERASE2;
1123                 case NAND_CMD_RESET:
1124                         return STATE_CMD_RESET;
1125                 case NAND_CMD_RNDOUT:
1126                         return STATE_CMD_RNDOUT;
1127                 case NAND_CMD_RNDOUTSTART:
1128                         return STATE_CMD_RNDOUTSTART;
1129         }
1130
1131         NS_ERR("get_state_by_command: unknown command, BUG\n");
1132         return 0;
1133 }
1134
1135 /*
1136  * Move an address byte to the correspondent internal register.
1137  */
1138 static inline void ns_accept_addr_byte(struct nandsim *ns, u_char bt)
1139 {
1140         uint byte = (uint)bt;
1141
1142         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1143                 ns->regs.column |= (byte << 8 * ns->regs.count);
1144         else {
1145                 ns->regs.row |= (byte << 8 * (ns->regs.count -
1146                                                 ns->geom.pgaddrbytes +
1147                                                 ns->geom.secaddrbytes));
1148         }
1149
1150         return;
1151 }
1152
1153 /*
1154  * Switch to STATE_READY state.
1155  */
1156 static inline void ns_switch_to_ready_state(struct nandsim *ns, u_char status)
1157 {
1158         NS_DBG("switch_to_ready_state: switch to %s state\n",
1159                ns_get_state_name(STATE_READY));
1160
1161         ns->state       = STATE_READY;
1162         ns->nxstate     = STATE_UNKNOWN;
1163         ns->op          = NULL;
1164         ns->npstates    = 0;
1165         ns->stateidx    = 0;
1166         ns->regs.num    = 0;
1167         ns->regs.count  = 0;
1168         ns->regs.off    = 0;
1169         ns->regs.row    = 0;
1170         ns->regs.column = 0;
1171         ns->regs.status = status;
1172 }
1173
1174 /*
1175  * If the operation isn't known yet, try to find it in the global array
1176  * of supported operations.
1177  *
1178  * Operation can be unknown because of the following.
1179  *   1. New command was accepted and this is the first call to find the
1180  *      correspondent states chain. In this case ns->npstates = 0;
1181  *   2. There are several operations which begin with the same command(s)
1182  *      (for example program from the second half and read from the
1183  *      second half operations both begin with the READ1 command). In this
1184  *      case the ns->pstates[] array contains previous states.
1185  *
1186  * Thus, the function tries to find operation containing the following
1187  * states (if the 'flag' parameter is 0):
1188  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1189  *
1190  * If (one and only one) matching operation is found, it is accepted (
1191  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1192  * zeroed).
1193  *
1194  * If there are several matches, the current state is pushed to the
1195  * ns->pstates.
1196  *
1197  * The operation can be unknown only while commands are input to the chip.
1198  * As soon as address command is accepted, the operation must be known.
1199  * In such situation the function is called with 'flag' != 0, and the
1200  * operation is searched using the following pattern:
1201  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1202  *
1203  * It is supposed that this pattern must either match one operation or
1204  * none. There can't be ambiguity in that case.
1205  *
1206  * If no matches found, the function does the following:
1207  *   1. if there are saved states present, try to ignore them and search
1208  *      again only using the last command. If nothing was found, switch
1209  *      to the STATE_READY state.
1210  *   2. if there are no saved states, switch to the STATE_READY state.
1211  *
1212  * RETURNS: -2 - no matched operations found.
1213  *          -1 - several matches.
1214  *           0 - operation is found.
1215  */
1216 static int ns_find_operation(struct nandsim *ns, uint32_t flag)
1217 {
1218         int opsfound = 0;
1219         int i, j, idx = 0;
1220
1221         for (i = 0; i < NS_OPER_NUM; i++) {
1222
1223                 int found = 1;
1224
1225                 if (!(ns->options & ops[i].reqopts))
1226                         /* Ignore operations we can't perform */
1227                         continue;
1228
1229                 if (flag) {
1230                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1231                                 continue;
1232                 } else {
1233                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1234                                 continue;
1235                 }
1236
1237                 for (j = 0; j < ns->npstates; j++)
1238                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1239                                 && (ns->options & ops[idx].reqopts)) {
1240                                 found = 0;
1241                                 break;
1242                         }
1243
1244                 if (found) {
1245                         idx = i;
1246                         opsfound += 1;
1247                 }
1248         }
1249
1250         if (opsfound == 1) {
1251                 /* Exact match */
1252                 ns->op = &ops[idx].states[0];
1253                 if (flag) {
1254                         /*
1255                          * In this case the find_operation function was
1256                          * called when address has just began input. But it isn't
1257                          * yet fully input and the current state must
1258                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1259                          * state must be the next state (ns->nxstate).
1260                          */
1261                         ns->stateidx = ns->npstates - 1;
1262                 } else {
1263                         ns->stateidx = ns->npstates;
1264                 }
1265                 ns->npstates = 0;
1266                 ns->state = ns->op[ns->stateidx];
1267                 ns->nxstate = ns->op[ns->stateidx + 1];
1268                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1269                        idx, ns_get_state_name(ns->state),
1270                        ns_get_state_name(ns->nxstate));
1271                 return 0;
1272         }
1273
1274         if (opsfound == 0) {
1275                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
1276                 if (ns->npstates != 0) {
1277                         NS_DBG("find_operation: no operation found, try again with state %s\n",
1278                                ns_get_state_name(ns->state));
1279                         ns->npstates = 0;
1280                         return ns_find_operation(ns, 0);
1281
1282                 }
1283                 NS_DBG("find_operation: no operations found\n");
1284                 ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1285                 return -2;
1286         }
1287
1288         if (flag) {
1289                 /* This shouldn't happen */
1290                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1291                 return -2;
1292         }
1293
1294         NS_DBG("find_operation: there is still ambiguity\n");
1295
1296         ns->pstates[ns->npstates++] = ns->state;
1297
1298         return -1;
1299 }
1300
1301 static void ns_put_pages(struct nandsim *ns)
1302 {
1303         int i;
1304
1305         for (i = 0; i < ns->held_cnt; i++)
1306                 put_page(ns->held_pages[i]);
1307 }
1308
1309 /* Get page cache pages in advance to provide NOFS memory allocation */
1310 static int ns_get_pages(struct nandsim *ns, struct file *file, size_t count,
1311                         loff_t pos)
1312 {
1313         pgoff_t index, start_index, end_index;
1314         struct page *page;
1315         struct address_space *mapping = file->f_mapping;
1316
1317         start_index = pos >> PAGE_SHIFT;
1318         end_index = (pos + count - 1) >> PAGE_SHIFT;
1319         if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1320                 return -EINVAL;
1321         ns->held_cnt = 0;
1322         for (index = start_index; index <= end_index; index++) {
1323                 page = find_get_page(mapping, index);
1324                 if (page == NULL) {
1325                         page = find_or_create_page(mapping, index, GFP_NOFS);
1326                         if (page == NULL) {
1327                                 write_inode_now(mapping->host, 1);
1328                                 page = find_or_create_page(mapping, index, GFP_NOFS);
1329                         }
1330                         if (page == NULL) {
1331                                 ns_put_pages(ns);
1332                                 return -ENOMEM;
1333                         }
1334                         unlock_page(page);
1335                 }
1336                 ns->held_pages[ns->held_cnt++] = page;
1337         }
1338         return 0;
1339 }
1340
1341 static ssize_t ns_read_file(struct nandsim *ns, struct file *file, void *buf,
1342                             size_t count, loff_t pos)
1343 {
1344         ssize_t tx;
1345         int err;
1346         unsigned int noreclaim_flag;
1347
1348         err = ns_get_pages(ns, file, count, pos);
1349         if (err)
1350                 return err;
1351         noreclaim_flag = memalloc_noreclaim_save();
1352         tx = kernel_read(file, buf, count, &pos);
1353         memalloc_noreclaim_restore(noreclaim_flag);
1354         ns_put_pages(ns);
1355         return tx;
1356 }
1357
1358 static ssize_t ns_write_file(struct nandsim *ns, struct file *file, void *buf,
1359                              size_t count, loff_t pos)
1360 {
1361         ssize_t tx;
1362         int err;
1363         unsigned int noreclaim_flag;
1364
1365         err = ns_get_pages(ns, file, count, pos);
1366         if (err)
1367                 return err;
1368         noreclaim_flag = memalloc_noreclaim_save();
1369         tx = kernel_write(file, buf, count, &pos);
1370         memalloc_noreclaim_restore(noreclaim_flag);
1371         ns_put_pages(ns);
1372         return tx;
1373 }
1374
1375 /*
1376  * Returns a pointer to the current page.
1377  */
1378 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1379 {
1380         return &(ns->pages[ns->regs.row]);
1381 }
1382
1383 /*
1384  * Retuns a pointer to the current byte, within the current page.
1385  */
1386 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1387 {
1388         return NS_GET_PAGE(ns)->byte + NS_PAGE_BYTE_SHIFT(ns);
1389 }
1390
1391 static int ns_do_read_error(struct nandsim *ns, int num)
1392 {
1393         unsigned int page_no = ns->regs.row;
1394
1395         if (ns_read_error(page_no)) {
1396                 prandom_bytes(ns->buf.byte, num);
1397                 NS_WARN("simulating read error in page %u\n", page_no);
1398                 return 1;
1399         }
1400         return 0;
1401 }
1402
1403 static void ns_do_bit_flips(struct nandsim *ns, int num)
1404 {
1405         if (bitflips && prandom_u32() < (1 << 22)) {
1406                 int flips = 1;
1407                 if (bitflips > 1)
1408                         flips = prandom_u32_max(bitflips) + 1;
1409                 while (flips--) {
1410                         int pos = prandom_u32_max(num * 8);
1411                         ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1412                         NS_WARN("read_page: flipping bit %d in page %d "
1413                                 "reading from %d ecc: corrected=%u failed=%u\n",
1414                                 pos, ns->regs.row, NS_PAGE_BYTE_SHIFT(ns),
1415                                 nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1416                 }
1417         }
1418 }
1419
1420 /*
1421  * Fill the NAND buffer with data read from the specified page.
1422  */
1423 static void ns_read_page(struct nandsim *ns, int num)
1424 {
1425         union ns_mem *mypage;
1426
1427         if (ns->cfile) {
1428                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1429                         NS_DBG("read_page: page %d not written\n", ns->regs.row);
1430                         memset(ns->buf.byte, 0xFF, num);
1431                 } else {
1432                         loff_t pos;
1433                         ssize_t tx;
1434
1435                         NS_DBG("read_page: page %d written, reading from %d\n",
1436                                 ns->regs.row, NS_PAGE_BYTE_SHIFT(ns));
1437                         if (ns_do_read_error(ns, num))
1438                                 return;
1439                         pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1440                         tx = ns_read_file(ns, ns->cfile, ns->buf.byte, num,
1441                                           pos);
1442                         if (tx != num) {
1443                                 NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1444                                 return;
1445                         }
1446                         ns_do_bit_flips(ns, num);
1447                 }
1448                 return;
1449         }
1450
1451         mypage = NS_GET_PAGE(ns);
1452         if (mypage->byte == NULL) {
1453                 NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1454                 memset(ns->buf.byte, 0xFF, num);
1455         } else {
1456                 NS_DBG("read_page: page %d allocated, reading from %d\n",
1457                         ns->regs.row, NS_PAGE_BYTE_SHIFT(ns));
1458                 if (ns_do_read_error(ns, num))
1459                         return;
1460                 memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1461                 ns_do_bit_flips(ns, num);
1462         }
1463 }
1464
1465 /*
1466  * Erase all pages in the specified sector.
1467  */
1468 static void ns_erase_sector(struct nandsim *ns)
1469 {
1470         union ns_mem *mypage;
1471         int i;
1472
1473         if (ns->cfile) {
1474                 for (i = 0; i < ns->geom.pgsec; i++)
1475                         if (__test_and_clear_bit(ns->regs.row + i,
1476                                                  ns->pages_written)) {
1477                                 NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1478                         }
1479                 return;
1480         }
1481
1482         mypage = NS_GET_PAGE(ns);
1483         for (i = 0; i < ns->geom.pgsec; i++) {
1484                 if (mypage->byte != NULL) {
1485                         NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1486                         kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1487                         mypage->byte = NULL;
1488                 }
1489                 mypage++;
1490         }
1491 }
1492
1493 /*
1494  * Program the specified page with the contents from the NAND buffer.
1495  */
1496 static int ns_prog_page(struct nandsim *ns, int num)
1497 {
1498         int i;
1499         union ns_mem *mypage;
1500         u_char *pg_off;
1501
1502         if (ns->cfile) {
1503                 loff_t off;
1504                 ssize_t tx;
1505                 int all;
1506
1507                 NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1508                 pg_off = ns->file_buf + NS_PAGE_BYTE_SHIFT(ns);
1509                 off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1510                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1511                         all = 1;
1512                         memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1513                 } else {
1514                         all = 0;
1515                         tx = ns_read_file(ns, ns->cfile, pg_off, num, off);
1516                         if (tx != num) {
1517                                 NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1518                                 return -1;
1519                         }
1520                 }
1521                 for (i = 0; i < num; i++)
1522                         pg_off[i] &= ns->buf.byte[i];
1523                 if (all) {
1524                         loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1525                         tx = ns_write_file(ns, ns->cfile, ns->file_buf,
1526                                            ns->geom.pgszoob, pos);
1527                         if (tx != ns->geom.pgszoob) {
1528                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1529                                 return -1;
1530                         }
1531                         __set_bit(ns->regs.row, ns->pages_written);
1532                 } else {
1533                         tx = ns_write_file(ns, ns->cfile, pg_off, num, off);
1534                         if (tx != num) {
1535                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1536                                 return -1;
1537                         }
1538                 }
1539                 return 0;
1540         }
1541
1542         mypage = NS_GET_PAGE(ns);
1543         if (mypage->byte == NULL) {
1544                 NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1545                 /*
1546                  * We allocate memory with GFP_NOFS because a flash FS may
1547                  * utilize this. If it is holding an FS lock, then gets here,
1548                  * then kernel memory alloc runs writeback which goes to the FS
1549                  * again and deadlocks. This was seen in practice.
1550                  */
1551                 mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1552                 if (mypage->byte == NULL) {
1553                         NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1554                         return -1;
1555                 }
1556                 memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1557         }
1558
1559         pg_off = NS_PAGE_BYTE_OFF(ns);
1560         for (i = 0; i < num; i++)
1561                 pg_off[i] &= ns->buf.byte[i];
1562
1563         return 0;
1564 }
1565
1566 /*
1567  * If state has any action bit, perform this action.
1568  *
1569  * RETURNS: 0 if success, -1 if error.
1570  */
1571 static int ns_do_state_action(struct nandsim *ns, uint32_t action)
1572 {
1573         int num;
1574         int busdiv = ns->busw == 8 ? 1 : 2;
1575         unsigned int erase_block_no, page_no;
1576
1577         action &= ACTION_MASK;
1578
1579         /* Check that page address input is correct */
1580         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1581                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1582                 return -1;
1583         }
1584
1585         switch (action) {
1586
1587         case ACTION_CPY:
1588                 /*
1589                  * Copy page data to the internal buffer.
1590                  */
1591
1592                 /* Column shouldn't be very large */
1593                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1594                         NS_ERR("do_state_action: column number is too large\n");
1595                         break;
1596                 }
1597                 num = ns->geom.pgszoob - NS_PAGE_BYTE_SHIFT(ns);
1598                 ns_read_page(ns, num);
1599
1600                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1601                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
1602
1603                 if (ns->regs.off == 0)
1604                         NS_LOG("read page %d\n", ns->regs.row);
1605                 else if (ns->regs.off < ns->geom.pgsz)
1606                         NS_LOG("read page %d (second half)\n", ns->regs.row);
1607                 else
1608                         NS_LOG("read OOB of page %d\n", ns->regs.row);
1609
1610                 NS_UDELAY(access_delay);
1611                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1612
1613                 break;
1614
1615         case ACTION_SECERASE:
1616                 /*
1617                  * Erase sector.
1618                  */
1619
1620                 if (ns->lines.wp) {
1621                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1622                         return -1;
1623                 }
1624
1625                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1626                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
1627                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1628                         return -1;
1629                 }
1630
1631                 ns->regs.row = (ns->regs.row <<
1632                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1633                 ns->regs.column = 0;
1634
1635                 erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1636
1637                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1638                                 ns->regs.row, NS_RAW_OFFSET(ns));
1639                 NS_LOG("erase sector %u\n", erase_block_no);
1640
1641                 ns_erase_sector(ns);
1642
1643                 NS_MDELAY(erase_delay);
1644
1645                 if (erase_block_wear)
1646                         ns_update_wear(erase_block_no);
1647
1648                 if (ns_erase_error(erase_block_no)) {
1649                         NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1650                         return -1;
1651                 }
1652
1653                 break;
1654
1655         case ACTION_PRGPAGE:
1656                 /*
1657                  * Program page - move internal buffer data to the page.
1658                  */
1659
1660                 if (ns->lines.wp) {
1661                         NS_WARN("do_state_action: device is write-protected, programm\n");
1662                         return -1;
1663                 }
1664
1665                 num = ns->geom.pgszoob - NS_PAGE_BYTE_SHIFT(ns);
1666                 if (num != ns->regs.count) {
1667                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1668                                         ns->regs.count, num);
1669                         return -1;
1670                 }
1671
1672                 if (ns_prog_page(ns, num) == -1)
1673                         return -1;
1674
1675                 page_no = ns->regs.row;
1676
1677                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1678                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1679                 NS_LOG("programm page %d\n", ns->regs.row);
1680
1681                 NS_UDELAY(programm_delay);
1682                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1683
1684                 if (ns_write_error(page_no)) {
1685                         NS_WARN("simulating write failure in page %u\n", page_no);
1686                         return -1;
1687                 }
1688
1689                 break;
1690
1691         case ACTION_ZEROOFF:
1692                 NS_DBG("do_state_action: set internal offset to 0\n");
1693                 ns->regs.off = 0;
1694                 break;
1695
1696         case ACTION_HALFOFF:
1697                 if (!(ns->options & OPT_PAGE512_8BIT)) {
1698                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1699                                 "byte page size 8x chips\n");
1700                         return -1;
1701                 }
1702                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1703                 ns->regs.off = ns->geom.pgsz/2;
1704                 break;
1705
1706         case ACTION_OOBOFF:
1707                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1708                 ns->regs.off = ns->geom.pgsz;
1709                 break;
1710
1711         default:
1712                 NS_DBG("do_state_action: BUG! unknown action\n");
1713         }
1714
1715         return 0;
1716 }
1717
1718 /*
1719  * Switch simulator's state.
1720  */
1721 static void ns_switch_state(struct nandsim *ns)
1722 {
1723         if (ns->op) {
1724                 /*
1725                  * The current operation have already been identified.
1726                  * Just follow the states chain.
1727                  */
1728
1729                 ns->stateidx += 1;
1730                 ns->state = ns->nxstate;
1731                 ns->nxstate = ns->op[ns->stateidx + 1];
1732
1733                 NS_DBG("switch_state: operation is known, switch to the next state, "
1734                         "state: %s, nxstate: %s\n",
1735                        ns_get_state_name(ns->state),
1736                        ns_get_state_name(ns->nxstate));
1737         } else {
1738                 /*
1739                  * We don't yet know which operation we perform.
1740                  * Try to identify it.
1741                  */
1742
1743                 /*
1744                  *  The only event causing the switch_state function to
1745                  *  be called with yet unknown operation is new command.
1746                  */
1747                 ns->state = ns_get_state_by_command(ns->regs.command);
1748
1749                 NS_DBG("switch_state: operation is unknown, try to find it\n");
1750
1751                 if (ns_find_operation(ns, 0))
1752                         return;
1753         }
1754
1755         /* See, whether we need to do some action */
1756         if ((ns->state & ACTION_MASK) &&
1757             ns_do_state_action(ns, ns->state) < 0) {
1758                 ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1759                 return;
1760         }
1761
1762         /* For 16x devices column means the page offset in words */
1763         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1764                 NS_DBG("switch_state: double the column number for 16x device\n");
1765                 ns->regs.column <<= 1;
1766         }
1767
1768         if (NS_STATE(ns->nxstate) == STATE_READY) {
1769                 /*
1770                  * The current state is the last. Return to STATE_READY
1771                  */
1772
1773                 u_char status = NS_STATUS_OK(ns);
1774
1775                 /* In case of data states, see if all bytes were input/output */
1776                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1777                         && ns->regs.count != ns->regs.num) {
1778                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
1779                                         ns->regs.num - ns->regs.count);
1780                         status = NS_STATUS_FAILED(ns);
1781                 }
1782
1783                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1784
1785                 ns_switch_to_ready_state(ns, status);
1786
1787                 return;
1788         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1789                 /*
1790                  * If the next state is data input/output, switch to it now
1791                  */
1792
1793                 ns->state      = ns->nxstate;
1794                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1795                 ns->regs.num   = ns->regs.count = 0;
1796
1797                 NS_DBG("switch_state: the next state is data I/O, switch, "
1798                         "state: %s, nxstate: %s\n",
1799                        ns_get_state_name(ns->state),
1800                        ns_get_state_name(ns->nxstate));
1801
1802                 /*
1803                  * Set the internal register to the count of bytes which
1804                  * are expected to be input or output
1805                  */
1806                 switch (NS_STATE(ns->state)) {
1807                         case STATE_DATAIN:
1808                         case STATE_DATAOUT:
1809                                 ns->regs.num = ns->geom.pgszoob - NS_PAGE_BYTE_SHIFT(ns);
1810                                 break;
1811
1812                         case STATE_DATAOUT_ID:
1813                                 ns->regs.num = ns->geom.idbytes;
1814                                 break;
1815
1816                         case STATE_DATAOUT_STATUS:
1817                                 ns->regs.count = ns->regs.num = 0;
1818                                 break;
1819
1820                         default:
1821                                 NS_ERR("switch_state: BUG! unknown data state\n");
1822                 }
1823
1824         } else if (ns->nxstate & STATE_ADDR_MASK) {
1825                 /*
1826                  * If the next state is address input, set the internal
1827                  * register to the number of expected address bytes
1828                  */
1829
1830                 ns->regs.count = 0;
1831
1832                 switch (NS_STATE(ns->nxstate)) {
1833                         case STATE_ADDR_PAGE:
1834                                 ns->regs.num = ns->geom.pgaddrbytes;
1835
1836                                 break;
1837                         case STATE_ADDR_SEC:
1838                                 ns->regs.num = ns->geom.secaddrbytes;
1839                                 break;
1840
1841                         case STATE_ADDR_ZERO:
1842                                 ns->regs.num = 1;
1843                                 break;
1844
1845                         case STATE_ADDR_COLUMN:
1846                                 /* Column address is always 2 bytes */
1847                                 ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1848                                 break;
1849
1850                         default:
1851                                 NS_ERR("switch_state: BUG! unknown address state\n");
1852                 }
1853         } else {
1854                 /*
1855                  * Just reset internal counters.
1856                  */
1857
1858                 ns->regs.num = 0;
1859                 ns->regs.count = 0;
1860         }
1861 }
1862
1863 static u_char ns_nand_read_byte(struct nand_chip *chip)
1864 {
1865         struct nandsim *ns = nand_get_controller_data(chip);
1866         u_char outb = 0x00;
1867
1868         /* Sanity and correctness checks */
1869         if (!ns->lines.ce) {
1870                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1871                 return outb;
1872         }
1873         if (ns->lines.ale || ns->lines.cle) {
1874                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1875                 return outb;
1876         }
1877         if (!(ns->state & STATE_DATAOUT_MASK)) {
1878                 NS_WARN("read_byte: unexpected data output cycle, state is %s return %#x\n",
1879                         ns_get_state_name(ns->state), (uint)outb);
1880                 return outb;
1881         }
1882
1883         /* Status register may be read as many times as it is wanted */
1884         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1885                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1886                 return ns->regs.status;
1887         }
1888
1889         /* Check if there is any data in the internal buffer which may be read */
1890         if (ns->regs.count == ns->regs.num) {
1891                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1892                 return outb;
1893         }
1894
1895         switch (NS_STATE(ns->state)) {
1896                 case STATE_DATAOUT:
1897                         if (ns->busw == 8) {
1898                                 outb = ns->buf.byte[ns->regs.count];
1899                                 ns->regs.count += 1;
1900                         } else {
1901                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1902                                 ns->regs.count += 2;
1903                         }
1904                         break;
1905                 case STATE_DATAOUT_ID:
1906                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1907                         outb = ns->ids[ns->regs.count];
1908                         ns->regs.count += 1;
1909                         break;
1910                 default:
1911                         BUG();
1912         }
1913
1914         if (ns->regs.count == ns->regs.num) {
1915                 NS_DBG("read_byte: all bytes were read\n");
1916
1917                 if (NS_STATE(ns->nxstate) == STATE_READY)
1918                         ns_switch_state(ns);
1919         }
1920
1921         return outb;
1922 }
1923
1924 static void ns_nand_write_byte(struct nand_chip *chip, u_char byte)
1925 {
1926         struct nandsim *ns = nand_get_controller_data(chip);
1927
1928         /* Sanity and correctness checks */
1929         if (!ns->lines.ce) {
1930                 NS_ERR("write_byte: chip is disabled, ignore write\n");
1931                 return;
1932         }
1933         if (ns->lines.ale && ns->lines.cle) {
1934                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1935                 return;
1936         }
1937
1938         if (ns->lines.cle == 1) {
1939                 /*
1940                  * The byte written is a command.
1941                  */
1942
1943                 if (byte == NAND_CMD_RESET) {
1944                         NS_LOG("reset chip\n");
1945                         ns_switch_to_ready_state(ns, NS_STATUS_OK(ns));
1946                         return;
1947                 }
1948
1949                 /* Check that the command byte is correct */
1950                 if (ns_check_command(byte)) {
1951                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1952                         return;
1953                 }
1954
1955                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1956                         || NS_STATE(ns->state) == STATE_DATAOUT) {
1957                         int row = ns->regs.row;
1958
1959                         ns_switch_state(ns);
1960                         if (byte == NAND_CMD_RNDOUT)
1961                                 ns->regs.row = row;
1962                 }
1963
1964                 /* Check if chip is expecting command */
1965                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
1966                         /* Do not warn if only 2 id bytes are read */
1967                         if (!(ns->regs.command == NAND_CMD_READID &&
1968                             NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
1969                                 /*
1970                                  * We are in situation when something else (not command)
1971                                  * was expected but command was input. In this case ignore
1972                                  * previous command(s)/state(s) and accept the last one.
1973                                  */
1974                                 NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, ignore previous states\n",
1975                                         (uint)byte,
1976                                         ns_get_state_name(ns->nxstate));
1977                         }
1978                         ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1979                 }
1980
1981                 NS_DBG("command byte corresponding to %s state accepted\n",
1982                         ns_get_state_name(ns_get_state_by_command(byte)));
1983                 ns->regs.command = byte;
1984                 ns_switch_state(ns);
1985
1986         } else if (ns->lines.ale == 1) {
1987                 /*
1988                  * The byte written is an address.
1989                  */
1990
1991                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
1992
1993                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
1994
1995                         if (ns_find_operation(ns, 1) < 0)
1996                                 return;
1997
1998                         if ((ns->state & ACTION_MASK) &&
1999                             ns_do_state_action(ns, ns->state) < 0) {
2000                                 ns_switch_to_ready_state(ns,
2001                                                          NS_STATUS_FAILED(ns));
2002                                 return;
2003                         }
2004
2005                         ns->regs.count = 0;
2006                         switch (NS_STATE(ns->nxstate)) {
2007                                 case STATE_ADDR_PAGE:
2008                                         ns->regs.num = ns->geom.pgaddrbytes;
2009                                         break;
2010                                 case STATE_ADDR_SEC:
2011                                         ns->regs.num = ns->geom.secaddrbytes;
2012                                         break;
2013                                 case STATE_ADDR_ZERO:
2014                                         ns->regs.num = 1;
2015                                         break;
2016                                 default:
2017                                         BUG();
2018                         }
2019                 }
2020
2021                 /* Check that chip is expecting address */
2022                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
2023                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, switch to STATE_READY\n",
2024                                (uint)byte, ns_get_state_name(ns->nxstate));
2025                         ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2026                         return;
2027                 }
2028
2029                 /* Check if this is expected byte */
2030                 if (ns->regs.count == ns->regs.num) {
2031                         NS_ERR("write_byte: no more address bytes expected\n");
2032                         ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2033                         return;
2034                 }
2035
2036                 ns_accept_addr_byte(ns, byte);
2037
2038                 ns->regs.count += 1;
2039
2040                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2041                                 (uint)byte, ns->regs.count, ns->regs.num);
2042
2043                 if (ns->regs.count == ns->regs.num) {
2044                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2045                         ns_switch_state(ns);
2046                 }
2047
2048         } else {
2049                 /*
2050                  * The byte written is an input data.
2051                  */
2052
2053                 /* Check that chip is expecting data input */
2054                 if (!(ns->state & STATE_DATAIN_MASK)) {
2055                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, switch to %s\n",
2056                                (uint)byte, ns_get_state_name(ns->state),
2057                                ns_get_state_name(STATE_READY));
2058                         ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2059                         return;
2060                 }
2061
2062                 /* Check if this is expected byte */
2063                 if (ns->regs.count == ns->regs.num) {
2064                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2065                                         ns->regs.num);
2066                         return;
2067                 }
2068
2069                 if (ns->busw == 8) {
2070                         ns->buf.byte[ns->regs.count] = byte;
2071                         ns->regs.count += 1;
2072                 } else {
2073                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2074                         ns->regs.count += 2;
2075                 }
2076         }
2077
2078         return;
2079 }
2080
2081 static void ns_nand_write_buf(struct nand_chip *chip, const u_char *buf,
2082                               int len)
2083 {
2084         struct nandsim *ns = nand_get_controller_data(chip);
2085
2086         /* Check that chip is expecting data input */
2087         if (!(ns->state & STATE_DATAIN_MASK)) {
2088                 NS_ERR("write_buf: data input isn't expected, state is %s, switch to STATE_READY\n",
2089                        ns_get_state_name(ns->state));
2090                 ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2091                 return;
2092         }
2093
2094         /* Check if these are expected bytes */
2095         if (ns->regs.count + len > ns->regs.num) {
2096                 NS_ERR("write_buf: too many input bytes\n");
2097                 ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2098                 return;
2099         }
2100
2101         memcpy(ns->buf.byte + ns->regs.count, buf, len);
2102         ns->regs.count += len;
2103
2104         if (ns->regs.count == ns->regs.num) {
2105                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2106         }
2107 }
2108
2109 static void ns_nand_read_buf(struct nand_chip *chip, u_char *buf, int len)
2110 {
2111         struct nandsim *ns = nand_get_controller_data(chip);
2112
2113         /* Sanity and correctness checks */
2114         if (!ns->lines.ce) {
2115                 NS_ERR("read_buf: chip is disabled\n");
2116                 return;
2117         }
2118         if (ns->lines.ale || ns->lines.cle) {
2119                 NS_ERR("read_buf: ALE or CLE pin is high\n");
2120                 return;
2121         }
2122         if (!(ns->state & STATE_DATAOUT_MASK)) {
2123                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2124                         ns_get_state_name(ns->state));
2125                 return;
2126         }
2127
2128         if (NS_STATE(ns->state) != STATE_DATAOUT) {
2129                 int i;
2130
2131                 for (i = 0; i < len; i++)
2132                         buf[i] = ns_nand_read_byte(chip);
2133
2134                 return;
2135         }
2136
2137         /* Check if these are expected bytes */
2138         if (ns->regs.count + len > ns->regs.num) {
2139                 NS_ERR("read_buf: too many bytes to read\n");
2140                 ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2141                 return;
2142         }
2143
2144         memcpy(buf, ns->buf.byte + ns->regs.count, len);
2145         ns->regs.count += len;
2146
2147         if (ns->regs.count == ns->regs.num) {
2148                 if (NS_STATE(ns->nxstate) == STATE_READY)
2149                         ns_switch_state(ns);
2150         }
2151
2152         return;
2153 }
2154
2155 static int ns_exec_op(struct nand_chip *chip, const struct nand_operation *op,
2156                       bool check_only)
2157 {
2158         int i;
2159         unsigned int op_id;
2160         const struct nand_op_instr *instr = NULL;
2161         struct nandsim *ns = nand_get_controller_data(chip);
2162
2163         if (check_only)
2164                 return 0;
2165
2166         ns->lines.ce = 1;
2167
2168         for (op_id = 0; op_id < op->ninstrs; op_id++) {
2169                 instr = &op->instrs[op_id];
2170                 ns->lines.cle = 0;
2171                 ns->lines.ale = 0;
2172
2173                 switch (instr->type) {
2174                 case NAND_OP_CMD_INSTR:
2175                         ns->lines.cle = 1;
2176                         ns_nand_write_byte(chip, instr->ctx.cmd.opcode);
2177                         break;
2178                 case NAND_OP_ADDR_INSTR:
2179                         ns->lines.ale = 1;
2180                         for (i = 0; i < instr->ctx.addr.naddrs; i++)
2181                                 ns_nand_write_byte(chip, instr->ctx.addr.addrs[i]);
2182                         break;
2183                 case NAND_OP_DATA_IN_INSTR:
2184                         ns_nand_read_buf(chip, instr->ctx.data.buf.in, instr->ctx.data.len);
2185                         break;
2186                 case NAND_OP_DATA_OUT_INSTR:
2187                         ns_nand_write_buf(chip, instr->ctx.data.buf.out, instr->ctx.data.len);
2188                         break;
2189                 case NAND_OP_WAITRDY_INSTR:
2190                         /* we are always ready */
2191                         break;
2192                 }
2193         }
2194
2195         return 0;
2196 }
2197
2198 static int ns_attach_chip(struct nand_chip *chip)
2199 {
2200         unsigned int eccsteps, eccbytes;
2201
2202         chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
2203         chip->ecc.algo = bch ? NAND_ECC_ALGO_BCH : NAND_ECC_ALGO_HAMMING;
2204
2205         if (!bch)
2206                 return 0;
2207
2208         if (!IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_BCH)) {
2209                 NS_ERR("BCH ECC support is disabled\n");
2210                 return -EINVAL;
2211         }
2212
2213         /* Use 512-byte ecc blocks */
2214         eccsteps = nsmtd->writesize / 512;
2215         eccbytes = ((bch * 13) + 7) / 8;
2216
2217         /* Do not bother supporting small page devices */
2218         if (nsmtd->oobsize < 64 || !eccsteps) {
2219                 NS_ERR("BCH not available on small page devices\n");
2220                 return -EINVAL;
2221         }
2222
2223         if (((eccbytes * eccsteps) + 2) > nsmtd->oobsize) {
2224                 NS_ERR("Invalid BCH value %u\n", bch);
2225                 return -EINVAL;
2226         }
2227
2228         chip->ecc.size = 512;
2229         chip->ecc.strength = bch;
2230         chip->ecc.bytes = eccbytes;
2231
2232         NS_INFO("Using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2233
2234         return 0;
2235 }
2236
2237 static const struct nand_controller_ops ns_controller_ops = {
2238         .attach_chip = ns_attach_chip,
2239         .exec_op = ns_exec_op,
2240 };
2241
2242 /*
2243  * Module initialization function
2244  */
2245 static int __init ns_init_module(void)
2246 {
2247         struct list_head *pos, *n;
2248         struct nand_chip *chip;
2249         struct nandsim *ns;
2250         int ret;
2251
2252         if (bus_width != 8 && bus_width != 16) {
2253                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2254                 return -EINVAL;
2255         }
2256
2257         ns = kzalloc(sizeof(struct nandsim), GFP_KERNEL);
2258         if (!ns) {
2259                 NS_ERR("unable to allocate core structures.\n");
2260                 return -ENOMEM;
2261         }
2262         chip        = &ns->chip;
2263         nsmtd       = nand_to_mtd(chip);
2264         nand_set_controller_data(chip, (void *)ns);
2265
2266         /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2267         /* and 'badblocks' parameters to work */
2268         chip->options   |= NAND_SKIP_BBTSCAN;
2269
2270         switch (bbt) {
2271         case 2:
2272                 chip->bbt_options |= NAND_BBT_NO_OOB;
2273                 fallthrough;
2274         case 1:
2275                 chip->bbt_options |= NAND_BBT_USE_FLASH;
2276                 fallthrough;
2277         case 0:
2278                 break;
2279         default:
2280                 NS_ERR("bbt has to be 0..2\n");
2281                 ret = -EINVAL;
2282                 goto free_ns_struct;
2283         }
2284         /*
2285          * Perform minimum nandsim structure initialization to handle
2286          * the initial ID read command correctly
2287          */
2288         if (id_bytes[6] != 0xFF || id_bytes[7] != 0xFF)
2289                 ns->geom.idbytes = 8;
2290         else if (id_bytes[4] != 0xFF || id_bytes[5] != 0xFF)
2291                 ns->geom.idbytes = 6;
2292         else if (id_bytes[2] != 0xFF || id_bytes[3] != 0xFF)
2293                 ns->geom.idbytes = 4;
2294         else
2295                 ns->geom.idbytes = 2;
2296         ns->regs.status = NS_STATUS_OK(ns);
2297         ns->nxstate = STATE_UNKNOWN;
2298         ns->options |= OPT_PAGE512; /* temporary value */
2299         memcpy(ns->ids, id_bytes, sizeof(ns->ids));
2300         if (bus_width == 16) {
2301                 ns->busw = 16;
2302                 chip->options |= NAND_BUSWIDTH_16;
2303         }
2304
2305         nsmtd->owner = THIS_MODULE;
2306
2307         ret = ns_parse_weakblocks();
2308         if (ret)
2309                 goto free_ns_struct;
2310
2311         ret = ns_parse_weakpages();
2312         if (ret)
2313                 goto free_wb_list;
2314
2315         ret = ns_parse_gravepages();
2316         if (ret)
2317                 goto free_wp_list;
2318
2319         nand_controller_init(&ns->base);
2320         ns->base.ops = &ns_controller_ops;
2321         chip->controller = &ns->base;
2322
2323         ret = nand_scan(chip, 1);
2324         if (ret) {
2325                 NS_ERR("Could not scan NAND Simulator device\n");
2326                 goto free_gp_list;
2327         }
2328
2329         if (overridesize) {
2330                 uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2331                 struct nand_memory_organization *memorg;
2332                 u64 targetsize;
2333
2334                 memorg = nanddev_get_memorg(&chip->base);
2335
2336                 if (new_size >> overridesize != nsmtd->erasesize) {
2337                         NS_ERR("overridesize is too big\n");
2338                         ret = -EINVAL;
2339                         goto cleanup_nand;
2340                 }
2341
2342                 /* N.B. This relies on nand_scan not doing anything with the size before we change it */
2343                 nsmtd->size = new_size;
2344                 memorg->eraseblocks_per_lun = 1 << overridesize;
2345                 targetsize = nanddev_target_size(&chip->base);
2346                 chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2347                 chip->pagemask = (targetsize >> chip->page_shift) - 1;
2348         }
2349
2350         ret = ns_setup_wear_reporting(nsmtd);
2351         if (ret)
2352                 goto cleanup_nand;
2353
2354         ret = ns_init(nsmtd);
2355         if (ret)
2356                 goto free_ebw;
2357
2358         ret = nand_create_bbt(chip);
2359         if (ret)
2360                 goto free_ns_object;
2361
2362         ret = ns_parse_badblocks(ns, nsmtd);
2363         if (ret)
2364                 goto free_ns_object;
2365
2366         /* Register NAND partitions */
2367         ret = mtd_device_register(nsmtd, &ns->partitions[0], ns->nbparts);
2368         if (ret)
2369                 goto free_ns_object;
2370
2371         ret = ns_debugfs_create(ns);
2372         if (ret)
2373                 goto unregister_mtd;
2374
2375         return 0;
2376
2377 unregister_mtd:
2378         WARN_ON(mtd_device_unregister(nsmtd));
2379 free_ns_object:
2380         ns_free(ns);
2381 free_ebw:
2382         kfree(erase_block_wear);
2383 cleanup_nand:
2384         nand_cleanup(chip);
2385 free_gp_list:
2386         list_for_each_safe(pos, n, &grave_pages) {
2387                 list_del(pos);
2388                 kfree(list_entry(pos, struct grave_page, list));
2389         }
2390 free_wp_list:
2391         list_for_each_safe(pos, n, &weak_pages) {
2392                 list_del(pos);
2393                 kfree(list_entry(pos, struct weak_page, list));
2394         }
2395 free_wb_list:
2396         list_for_each_safe(pos, n, &weak_blocks) {
2397                 list_del(pos);
2398                 kfree(list_entry(pos, struct weak_block, list));
2399         }
2400 free_ns_struct:
2401         kfree(ns);
2402
2403         return ret;
2404 }
2405
2406 module_init(ns_init_module);
2407
2408 /*
2409  * Module clean-up function
2410  */
2411 static void __exit ns_cleanup_module(void)
2412 {
2413         struct nand_chip *chip = mtd_to_nand(nsmtd);
2414         struct nandsim *ns = nand_get_controller_data(chip);
2415         struct list_head *pos, *n;
2416
2417         ns_debugfs_remove(ns);
2418         WARN_ON(mtd_device_unregister(nsmtd));
2419         ns_free(ns);
2420         kfree(erase_block_wear);
2421         nand_cleanup(chip);
2422
2423         list_for_each_safe(pos, n, &grave_pages) {
2424                 list_del(pos);
2425                 kfree(list_entry(pos, struct grave_page, list));
2426         }
2427
2428         list_for_each_safe(pos, n, &weak_pages) {
2429                 list_del(pos);
2430                 kfree(list_entry(pos, struct weak_page, list));
2431         }
2432
2433         list_for_each_safe(pos, n, &weak_blocks) {
2434                 list_del(pos);
2435                 kfree(list_entry(pos, struct weak_block, list));
2436         }
2437
2438         kfree(ns);
2439 }
2440
2441 module_exit(ns_cleanup_module);
2442
2443 MODULE_LICENSE ("GPL");
2444 MODULE_AUTHOR ("Artem B. Bityuckiy");
2445 MODULE_DESCRIPTION ("The NAND flash simulator");