drivers/mtd/nand/nandsim.c

   1 /*
   2  * NAND flash simulator.
   3  *
   4  * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org>
   5  *
   6  * Copyright (C) 2004 Nokia Corporation
   7  *
   8  * Note: NS means "NAND Simulator".
   9  * Note: Input means input TO flash chip, output means output FROM chip.
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU General Public License as published by the
  13  * Free Software Foundation; either version 2, or (at your option) any later
  14  * version.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
  19  * Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
  24  *
  25  * $Id: nandsim.c,v 1.8 2005/03/19 15:33:56 dedekind Exp $
  26  */
  27
  28 #include <linux/config.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/module.h>
  32 #include <linux/moduleparam.h>
  33 #include <linux/vmalloc.h>
  34 #include <linux/slab.h>
  35 #include <linux/errno.h>
  36 #include <linux/string.h>
  37 #include <linux/mtd/mtd.h>
  38 #include <linux/mtd/nand.h>
  39 #include <linux/mtd/partitions.h>
  40 #include <linux/delay.h>
  41 #ifdef CONFIG_NS_ABS_POS
  42 #include <asm/io.h>
  43 #endif
  44
  45
  46 /* Default simulator parameters values */
  47 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
  48     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
  49     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
  50     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
  51 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
  52 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
  53 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
  54 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
  55 #endif
  56
  57 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
  58 #define CONFIG_NANDSIM_ACCESS_DELAY 25
  59 #endif
  60 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
  61 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
  62 #endif
  63 #ifndef CONFIG_NANDSIM_ERASE_DELAY
  64 #define CONFIG_NANDSIM_ERASE_DELAY 2
  65 #endif
  66 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
  67 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
  68 #endif
  69 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
  70 #define CONFIG_NANDSIM_INPUT_CYCLE  50
  71 #endif
  72 #ifndef CONFIG_NANDSIM_BUS_WIDTH
  73 #define CONFIG_NANDSIM_BUS_WIDTH  8
  74 #endif
  75 #ifndef CONFIG_NANDSIM_DO_DELAYS
  76 #define CONFIG_NANDSIM_DO_DELAYS  0
  77 #endif
  78 #ifndef CONFIG_NANDSIM_LOG
  79 #define CONFIG_NANDSIM_LOG        0
  80 #endif
  81 #ifndef CONFIG_NANDSIM_DBG
  82 #define CONFIG_NANDSIM_DBG        0
  83 #endif
  84
  85 static uint first_id_byte  = CONFIG_NANDSIM_FIRST_ID_BYTE;
  86 static uint second_id_byte = CONFIG_NANDSIM_SECOND_ID_BYTE;
  87 static uint third_id_byte  = CONFIG_NANDSIM_THIRD_ID_BYTE;
  88 static uint fourth_id_byte = CONFIG_NANDSIM_FOURTH_ID_BYTE;
  89 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
  90 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
  91 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
  92 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
  93 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
  94 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
  95 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
  96 static uint log            = CONFIG_NANDSIM_LOG;
  97 static uint dbg            = CONFIG_NANDSIM_DBG;
  98
  99 module_param(first_id_byte,  uint, 0400);
 100 module_param(second_id_byte, uint, 0400);
 101 module_param(third_id_byte,  uint, 0400);
 102 module_param(fourth_id_byte, uint, 0400);
 103 module_param(access_delay,   uint, 0400);
 104 module_param(programm_delay, uint, 0400);
 105 module_param(erase_delay,    uint, 0400);
 106 module_param(output_cycle,   uint, 0400);
 107 module_param(input_cycle,    uint, 0400);
 108 module_param(bus_width,      uint, 0400);
 109 module_param(do_delays,      uint, 0400);
 110 module_param(log,            uint, 0400);
 111 module_param(dbg,            uint, 0400);
 112
 113 MODULE_PARM_DESC(first_id_byte,  "The fist byte returned by NAND Flash 'read ID' command (manufaturer ID)");
 114 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID)");
 115 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command");
 116 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command");
 117 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microiseconds)");
 118 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
 119 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
 120 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanodeconds)");
 121 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanodeconds)");
 122 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
 123 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
 124 MODULE_PARM_DESC(log,            "Perform logging if not zero");
 125 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
 126
 127 /* The largest possible page size */
 128 #define NS_LARGEST_PAGE_SIZE    2048
 129
 130 /* The prefix for simulator output */
 131 #define NS_OUTPUT_PREFIX "[nandsim]"
 132
 133 /* Simulator's output macros (logging, debugging, warning, error) */
 134 #define NS_LOG(args...) \
 135         do { if (log) printk(KERN_DEBUG NS_OUTPUT_PREFIX " log: " args); } while(0)
 136 #define NS_DBG(args...) \
 137         do { if (dbg) printk(KERN_DEBUG NS_OUTPUT_PREFIX " debug: " args); } while(0)
 138 #define NS_WARN(args...) \
 139         do { printk(KERN_WARNING NS_OUTPUT_PREFIX " warnig: " args); } while(0)
 140 #define NS_ERR(args...) \
 141         do { printk(KERN_ERR NS_OUTPUT_PREFIX " errorr: " args); } while(0)
 142
 143 /* Busy-wait delay macros (microseconds, milliseconds) */
 144 #define NS_UDELAY(us) \
 145         do { if (do_delays) udelay(us); } while(0)
 146 #define NS_MDELAY(us) \
 147         do { if (do_delays) mdelay(us); } while(0)
 148
 149 /* Is the nandsim structure initialized ? */
 150 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
 151
 152 /* Good operation completion status */
 153 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
 154
 155 /* Operation failed completion status */
 156 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
 157
 158 /* Calculate the page offset in flash RAM image by (row, column) address */
 159 #define NS_RAW_OFFSET(ns) \
 160         (((ns)->regs.row << (ns)->geom.pgshift) + ((ns)->regs.row * (ns)->geom.oobsz) + (ns)->regs.column)
 161
 162 /* Calculate the OOB offset in flash RAM image by (row, column) address */
 163 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
 164
 165 /* After a command is input, the simulator goes to one of the following states */
 166 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
 167 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
 168 #define STATE_CMD_READSTART      0x00000003 /* read data second command (large page devices) */
 169 #define STATE_CMD_PAGEPROG     0x00000004 /* start page programm */
 170 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
 171 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
 172 #define STATE_CMD_STATUS       0x00000007 /* read status */
 173 #define STATE_CMD_STATUS_M     0x00000008 /* read multi-plane status (isn't implemented) */
 174 #define STATE_CMD_SEQIN        0x00000009 /* sequential data imput */
 175 #define STATE_CMD_READID       0x0000000A /* read ID */
 176 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
 177 #define STATE_CMD_RESET        0x0000000C /* reset */
 178 #define STATE_CMD_MASK         0x0000000F /* command states mask */
 179
 180 /* After an addres is input, the simulator goes to one of these states */
 181 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
 182 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
 183 #define STATE_ADDR_ZERO        0x00000030 /* one byte zero address was accepted */
 184 #define STATE_ADDR_MASK        0x00000030 /* address states mask */
 185
 186 /* Durind data input/output the simulator is in these states */
 187 #define STATE_DATAIN           0x00000100 /* waiting for data input */
 188 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
 189
 190 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
 191 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
 192 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
 193 #define STATE_DATAOUT_STATUS_M 0x00004000 /* waiting for multi-plane status output */
 194 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
 195
 196 /* Previous operation is done, ready to accept new requests */
 197 #define STATE_READY            0x00000000
 198
 199 /* This state is used to mark that the next state isn't known yet */
 200 #define STATE_UNKNOWN          0x10000000
 201
 202 /* Simulator's actions bit masks */
 203 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
 204 #define ACTION_PRGPAGE   0x00200000 /* programm the internal buffer to flash */
 205 #define ACTION_SECERASE  0x00300000 /* erase sector */
 206 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
 207 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
 208 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
 209 #define ACTION_MASK      0x00700000 /* action mask */
 210
 211 #define NS_OPER_NUM      12 /* Number of operations supported by the simulator */
 212 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
 213
 214 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
 215 #define OPT_PAGE256      0x00000001 /* 256-byte  page chips */
 216 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
 217 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
 218 #define OPT_SMARTMEDIA   0x00000010 /* SmartMedia technology chips */
 219 #define OPT_AUTOINCR     0x00000020 /* page number auto inctimentation is possible */
 220 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
 221 #define OPT_LARGEPAGE    (OPT_PAGE2048) /* 2048-byte page chips */
 222 #define OPT_SMALLPAGE    (OPT_PAGE256  | OPT_PAGE512)  /* 256 and 512-byte page chips */
 223
 224 /* Remove action bits ftom state */
 225 #define NS_STATE(x) ((x) & ~ACTION_MASK)
 226
 227 /*
 228  * Maximum previous states which need to be saved. Currently saving is
 229  * only needed for page programm operation with preceeded read command
 230  * (which is only valid for 512-byte pages).
 231  */
 232 #define NS_MAX_PREVSTATES 1
 233
 234 /*
 235  * The structure which describes all the internal simulator data.
 236  */
 237 struct nandsim {
 238         struct mtd_partition part;
 239
 240         uint busw;              /* flash chip bus width (8 or 16) */
 241         u_char ids[4];          /* chip's ID bytes */
 242         uint32_t options;       /* chip's characteristic bits */
 243         uint32_t state;         /* current chip state */
 244         uint32_t nxstate;       /* next expected state */
 245
 246         uint32_t *op;           /* current operation, NULL operations isn't known yet  */
 247         uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
 248         uint16_t npstates;      /* number of previous states saved */
 249         uint16_t stateidx;      /* current state index */
 250
 251         /* The simulated NAND flash image */
 252         union flash_media {
 253                 u_char *byte;
 254                 uint16_t    *word;
 255         } mem;
 256
 257         /* Internal buffer of page + OOB size bytes */
 258         union internal_buffer {
 259                 u_char *byte;    /* for byte access */
 260                 uint16_t *word;  /* for 16-bit word access */
 261         } buf;
 262
 263         /* NAND flash "geometry" */
 264         struct nandsin_geometry {
 265                 uint32_t totsz;     /* total flash size, bytes */
 266                 uint32_t secsz;     /* flash sector (erase block) size, bytes */
 267                 uint pgsz;          /* NAND flash page size, bytes */
 268                 uint oobsz;         /* page OOB area size, bytes */
 269                 uint32_t totszoob;  /* total flash size including OOB, bytes */
 270                 uint pgszoob;       /* page size including OOB , bytes*/
 271                 uint secszoob;      /* sector size including OOB, bytes */
 272                 uint pgnum;         /* total number of pages */
 273                 uint pgsec;         /* number of pages per sector */
 274                 uint secshift;      /* bits number in sector size */
 275                 uint pgshift;       /* bits number in page size */
 276                 uint oobshift;      /* bits number in OOB size */
 277                 uint pgaddrbytes;   /* bytes per page address */
 278                 uint secaddrbytes;  /* bytes per sector address */
 279                 uint idbytes;       /* the number ID bytes that this chip outputs */
 280         } geom;
 281
 282         /* NAND flash internal registers */
 283         struct nandsim_regs {
 284                 unsigned command; /* the command register */
 285                 u_char   status;  /* the status register */
 286                 uint     row;     /* the page number */
 287                 uint     column;  /* the offset within page */
 288                 uint     count;   /* internal counter */
 289                 uint     num;     /* number of bytes which must be processed */
 290                 uint     off;     /* fixed page offset */
 291         } regs;
 292
 293         /* NAND flash lines state */
 294         struct ns_lines_status {
 295                 int ce;  /* chip Enable */
 296                 int cle; /* command Latch Enable */
 297                 int ale; /* address Latch Enable */
 298                 int wp;  /* write Protect */
 299         } lines;
 300 };
 301
 302 /*
 303  * Operations array. To perform any operation the simulator must pass
 304  * through the correspondent states chain.
 305  */
 306 static struct nandsim_operations {
 307         uint32_t reqopts;  /* options which are required to perform the operation */
 308         uint32_t states[NS_OPER_STATES]; /* operation's states */
 309 } ops[NS_OPER_NUM] = {
 310         /* Read page + OOB from the beginning */
 311         {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
 312                         STATE_DATAOUT, STATE_READY}},
 313         /* Read page + OOB from the second half */
 314         {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
 315                         STATE_DATAOUT, STATE_READY}},
 316         /* Read OOB */
 317         {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
 318                         STATE_DATAOUT, STATE_READY}},
 319         /* Programm page starting from the beginning */
 320         {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
 321                         STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 322         /* Programm page starting from the beginning */
 323         {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
 324                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 325         /* Programm page starting from the second half */
 326         {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
 327                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 328         /* Programm OOB */
 329         {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
 330                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 331         /* Erase sector */
 332         {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
 333         /* Read status */
 334         {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
 335         /* Read multi-plane status */
 336         {OPT_SMARTMEDIA, {STATE_CMD_STATUS_M, STATE_DATAOUT_STATUS_M, STATE_READY}},
 337         /* Read ID */
 338         {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
 339         /* Large page devices read page */
 340         {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
 341                                STATE_DATAOUT, STATE_READY}}
 342 };
 343
 344 /* MTD structure for NAND controller */
 345 static struct mtd_info *nsmtd;
 346
 347 static u_char ns_verify_buf[NS_LARGEST_PAGE_SIZE];
 348
 349 /*
 350  * Initialize the nandsim structure.
 351  *
 352  * RETURNS: 0 if success, -ERRNO if failure.
 353  */
 354 static int
 355 init_nandsim(struct mtd_info *mtd)
 356 {
 357         struct nand_chip *chip = (struct nand_chip *)mtd->priv;
 358         struct nandsim   *ns   = (struct nandsim *)(chip->priv);
 359         int i;
 360
 361         if (NS_IS_INITIALIZED(ns)) {
 362                 NS_ERR("init_nandsim: nandsim is already initialized\n");
 363                 return -EIO;
 364         }
 365
 366         /* Force mtd to not do delays */
 367         chip->chip_delay = 0;
 368
 369         /* Initialize the NAND flash parameters */
 370         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
 371         ns->geom.totsz    = mtd->size;
 372         ns->geom.pgsz     = mtd->oobblock;
 373         ns->geom.oobsz    = mtd->oobsize;
 374         ns->geom.secsz    = mtd->erasesize;
 375         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
 376         ns->geom.pgnum    = ns->geom.totsz / ns->geom.pgsz;
 377         ns->geom.totszoob = ns->geom.totsz + ns->geom.pgnum * ns->geom.oobsz;
 378         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
 379         ns->geom.pgshift  = chip->page_shift;
 380         ns->geom.oobshift = ffs(ns->geom.oobsz) - 1;
 381         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
 382         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
 383         ns->options = 0;
 384
 385         if (ns->geom.pgsz == 256) {
 386                 ns->options |= OPT_PAGE256;
 387         }
 388         else if (ns->geom.pgsz == 512) {
 389                 ns->options |= (OPT_PAGE512 | OPT_AUTOINCR);
 390                 if (ns->busw == 8)
 391                         ns->options |= OPT_PAGE512_8BIT;
 392         } else if (ns->geom.pgsz == 2048) {
 393                 ns->options |= OPT_PAGE2048;
 394         } else {
 395                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
 396                 return -EIO;
 397         }
 398
 399         if (ns->options & OPT_SMALLPAGE) {
 400                 if (ns->geom.totsz < (64 << 20)) {
 401                         ns->geom.pgaddrbytes  = 3;
 402                         ns->geom.secaddrbytes = 2;
 403                 } else {
 404                         ns->geom.pgaddrbytes  = 4;
 405                         ns->geom.secaddrbytes = 3;
 406                 }
 407         } else {
 408                 if (ns->geom.totsz <= (128 << 20)) {
 409                         ns->geom.pgaddrbytes  = 5;
 410                         ns->geom.secaddrbytes = 2;
 411                 } else {
 412                         ns->geom.pgaddrbytes  = 5;
 413                         ns->geom.secaddrbytes = 3;
 414                 }
 415         }
 416
 417         /* Detect how many ID bytes the NAND chip outputs */
 418         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
 419                 if (second_id_byte != nand_flash_ids[i].id)
 420                         continue;
 421                 if (!(nand_flash_ids[i].options & NAND_NO_AUTOINCR))
 422                         ns->options |= OPT_AUTOINCR;
 423         }
 424
 425         if (ns->busw == 16)
 426                 NS_WARN("16-bit flashes support wasn't tested\n");
 427
 428         printk("flash size: %u MiB\n",          ns->geom.totsz >> 20);
 429         printk("page size: %u bytes\n",         ns->geom.pgsz);
 430         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
 431         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
 432         printk("pages number: %u\n",            ns->geom.pgnum);
 433         printk("pages per sector: %u\n",        ns->geom.pgsec);
 434         printk("bus width: %u\n",               ns->busw);
 435         printk("bits in sector size: %u\n",     ns->geom.secshift);
 436         printk("bits in page size: %u\n",       ns->geom.pgshift);
 437         printk("bits in OOB size: %u\n",        ns->geom.oobshift);
 438         printk("flash size with OOB: %u KiB\n", ns->geom.totszoob >> 10);
 439         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
 440         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
 441         printk("options: %#x\n",                ns->options);
 442
 443         /* Map / allocate and initialize the flash image */
 444 #ifdef CONFIG_NS_ABS_POS
 445         ns->mem.byte = ioremap(CONFIG_NS_ABS_POS, ns->geom.totszoob);
 446         if (!ns->mem.byte) {
 447                 NS_ERR("init_nandsim: failed to map the NAND flash image at address %p\n",
 448                         (void *)CONFIG_NS_ABS_POS);
 449                 return -ENOMEM;
 450         }
 451 #else
 452         ns->mem.byte = vmalloc(ns->geom.totszoob);
 453         if (!ns->mem.byte) {
 454                 NS_ERR("init_nandsim: unable to allocate %u bytes for flash image\n",
 455                         ns->geom.totszoob);
 456                 return -ENOMEM;
 457         }
 458         memset(ns->mem.byte, 0xFF, ns->geom.totszoob);
 459 #endif
 460
 461         /* Allocate / initialize the internal buffer */
 462         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 463         if (!ns->buf.byte) {
 464                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
 465                         ns->geom.pgszoob);
 466                 goto error;
 467         }
 468         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
 469
 470         /* Fill the partition_info structure */
 471         ns->part.name   = "NAND simulator partition";
 472         ns->part.offset = 0;
 473         ns->part.size   = ns->geom.totsz;
 474
 475         return 0;
 476
 477 error:
 478 #ifdef CONFIG_NS_ABS_POS
 479         iounmap(ns->mem.byte);
 480 #else
 481         vfree(ns->mem.byte);
 482 #endif
 483
 484         return -ENOMEM;
 485 }
 486
 487 /*
 488  * Free the nandsim structure.
 489  */
 490 static void
 491 free_nandsim(struct nandsim *ns)
 492 {
 493         kfree(ns->buf.byte);
 494
 495 #ifdef CONFIG_NS_ABS_POS
 496         iounmap(ns->mem.byte);
 497 #else
 498         vfree(ns->mem.byte);
 499 #endif
 500
 501         return;
 502 }
 503
 504 /*
 505  * Returns the string representation of 'state' state.
 506  */
 507 static char *
 508 get_state_name(uint32_t state)
 509 {
 510         switch (NS_STATE(state)) {
 511                 case STATE_CMD_READ0:
 512                         return "STATE_CMD_READ0";
 513                 case STATE_CMD_READ1:
 514                         return "STATE_CMD_READ1";
 515                 case STATE_CMD_PAGEPROG:
 516                         return "STATE_CMD_PAGEPROG";
 517                 case STATE_CMD_READOOB:
 518                         return "STATE_CMD_READOOB";
 519                 case STATE_CMD_READSTART:
 520                         return "STATE_CMD_READSTART";
 521                 case STATE_CMD_ERASE1:
 522                         return "STATE_CMD_ERASE1";
 523                 case STATE_CMD_STATUS:
 524                         return "STATE_CMD_STATUS";
 525                 case STATE_CMD_STATUS_M:
 526                         return "STATE_CMD_STATUS_M";
 527                 case STATE_CMD_SEQIN:
 528                         return "STATE_CMD_SEQIN";
 529                 case STATE_CMD_READID:
 530                         return "STATE_CMD_READID";
 531                 case STATE_CMD_ERASE2:
 532                         return "STATE_CMD_ERASE2";
 533                 case STATE_CMD_RESET:
 534                         return "STATE_CMD_RESET";
 535                 case STATE_ADDR_PAGE:
 536                         return "STATE_ADDR_PAGE";
 537                 case STATE_ADDR_SEC:
 538                         return "STATE_ADDR_SEC";
 539                 case STATE_ADDR_ZERO:
 540                         return "STATE_ADDR_ZERO";
 541                 case STATE_DATAIN:
 542                         return "STATE_DATAIN";
 543                 case STATE_DATAOUT:
 544                         return "STATE_DATAOUT";
 545                 case STATE_DATAOUT_ID:
 546                         return "STATE_DATAOUT_ID";
 547                 case STATE_DATAOUT_STATUS:
 548                         return "STATE_DATAOUT_STATUS";
 549                 case STATE_DATAOUT_STATUS_M:
 550                         return "STATE_DATAOUT_STATUS_M";
 551                 case STATE_READY:
 552                         return "STATE_READY";
 553                 case STATE_UNKNOWN:
 554                         return "STATE_UNKNOWN";
 555         }
 556
 557         NS_ERR("get_state_name: unknown state, BUG\n");
 558         return NULL;
 559 }
 560
 561 /*
 562  * Check if command is valid.
 563  *
 564  * RETURNS: 1 if wrong command, 0 if right.
 565  */
 566 static int
 567 check_command(int cmd)
 568 {
 569         switch (cmd) {
 570
 571         case NAND_CMD_READ0:
 572         case NAND_CMD_READSTART:
 573         case NAND_CMD_PAGEPROG:
 574         case NAND_CMD_READOOB:
 575         case NAND_CMD_ERASE1:
 576         case NAND_CMD_STATUS:
 577         case NAND_CMD_SEQIN:
 578         case NAND_CMD_READID:
 579         case NAND_CMD_ERASE2:
 580         case NAND_CMD_RESET:
 581         case NAND_CMD_READ1:
 582                 return 0;
 583
 584         case NAND_CMD_STATUS_MULTI:
 585         default:
 586                 return 1;
 587         }
 588 }
 589
 590 /*
 591  * Returns state after command is accepted by command number.
 592  */
 593 static uint32_t
 594 get_state_by_command(unsigned command)
 595 {
 596         switch (command) {
 597                 case NAND_CMD_READ0:
 598                         return STATE_CMD_READ0;
 599                 case NAND_CMD_READ1:
 600                         return STATE_CMD_READ1;
 601                 case NAND_CMD_PAGEPROG:
 602                         return STATE_CMD_PAGEPROG;
 603                 case NAND_CMD_READSTART:
 604                         return STATE_CMD_READSTART;
 605                 case NAND_CMD_READOOB:
 606                         return STATE_CMD_READOOB;
 607                 case NAND_CMD_ERASE1:
 608                         return STATE_CMD_ERASE1;
 609                 case NAND_CMD_STATUS:
 610                         return STATE_CMD_STATUS;
 611                 case NAND_CMD_STATUS_MULTI:
 612                         return STATE_CMD_STATUS_M;
 613                 case NAND_CMD_SEQIN:
 614                         return STATE_CMD_SEQIN;
 615                 case NAND_CMD_READID:
 616                         return STATE_CMD_READID;
 617                 case NAND_CMD_ERASE2:
 618                         return STATE_CMD_ERASE2;
 619                 case NAND_CMD_RESET:
 620                         return STATE_CMD_RESET;
 621         }
 622
 623         NS_ERR("get_state_by_command: unknown command, BUG\n");
 624         return 0;
 625 }
 626
 627 /*
 628  * Move an address byte to the correspondent internal register.
 629  */
 630 static inline void
 631 accept_addr_byte(struct nandsim *ns, u_char bt)
 632 {
 633         uint byte = (uint)bt;
 634
 635         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
 636                 ns->regs.column |= (byte << 8 * ns->regs.count);
 637         else {
 638                 ns->regs.row |= (byte << 8 * (ns->regs.count -
 639                                                 ns->geom.pgaddrbytes +
 640                                                 ns->geom.secaddrbytes));
 641         }
 642
 643         return;
 644 }
 645
 646 /*
 647  * Switch to STATE_READY state.
 648  */
 649 static inline void
 650 switch_to_ready_state(struct nandsim *ns, u_char status)
 651 {
 652         NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
 653
 654         ns->state       = STATE_READY;
 655         ns->nxstate     = STATE_UNKNOWN;
 656         ns->op          = NULL;
 657         ns->npstates    = 0;
 658         ns->stateidx    = 0;
 659         ns->regs.num    = 0;
 660         ns->regs.count  = 0;
 661         ns->regs.off    = 0;
 662         ns->regs.row    = 0;
 663         ns->regs.column = 0;
 664         ns->regs.status = status;
 665 }
 666
 667 /*
 668  * If the operation isn't known yet, try to find it in the global array
 669  * of supported operations.
 670  *
 671  * Operation can be unknown because of the following.
 672  *   1. New command was accepted and this is the firs call to find the
 673  *      correspondent states chain. In this case ns->npstates = 0;
 674  *   2. There is several operations which begin with the same command(s)
 675  *      (for example program from the second half and read from the
 676  *      second half operations both begin with the READ1 command). In this
 677  *      case the ns->pstates[] array contains previous states.
 678  *
 679  * Thus, the function tries to find operation containing the following
 680  * states (if the 'flag' parameter is 0):
 681  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
 682  *
 683  * If (one and only one) matching operation is found, it is accepted (
 684  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
 685  * zeroed).
 686  *
 687  * If there are several maches, the current state is pushed to the
 688  * ns->pstates.
 689  *
 690  * The operation can be unknown only while commands are input to the chip.
 691  * As soon as address command is accepted, the operation must be known.
 692  * In such situation the function is called with 'flag' != 0, and the
 693  * operation is searched using the following pattern:
 694  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
 695  *
 696  * It is supposed that this pattern must either match one operation on
 697  * none. There can't be ambiguity in that case.
 698  *
 699  * If no matches found, the functions does the following:
 700  *   1. if there are saved states present, try to ignore them and search
 701  *      again only using the last command. If nothing was found, switch
 702  *      to the STATE_READY state.
 703  *   2. if there are no saved states, switch to the STATE_READY state.
 704  *
 705  * RETURNS: -2 - no matched operations found.
 706  *          -1 - several matches.
 707  *           0 - operation is found.
 708  */
 709 static int
 710 find_operation(struct nandsim *ns, uint32_t flag)
 711 {
 712         int opsfound = 0;
 713         int i, j, idx = 0;
 714
 715         for (i = 0; i < NS_OPER_NUM; i++) {
 716
 717                 int found = 1;
 718
 719                 if (!(ns->options & ops[i].reqopts))
 720                         /* Ignore operations we can't perform */
 721                         continue;
 722
 723                 if (flag) {
 724                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
 725                                 continue;
 726                 } else {
 727                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
 728                                 continue;
 729                 }
 730
 731                 for (j = 0; j < ns->npstates; j++)
 732                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
 733                                 && (ns->options & ops[idx].reqopts)) {
 734                                 found = 0;
 735                                 break;
 736                         }
 737
 738                 if (found) {
 739                         idx = i;
 740                         opsfound += 1;
 741                 }
 742         }
 743
 744         if (opsfound == 1) {
 745                 /* Exact match */
 746                 ns->op = &ops[idx].states[0];
 747                 if (flag) {
 748                         /*
 749                          * In this case the find_operation function was
 750                          * called when address has just began input. But it isn't
 751                          * yet fully input and the current state must
 752                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
 753                          * state must be the next state (ns->nxstate).
 754                          */
 755                         ns->stateidx = ns->npstates - 1;
 756                 } else {
 757                         ns->stateidx = ns->npstates;
 758                 }
 759                 ns->npstates = 0;
 760                 ns->state = ns->op[ns->stateidx];
 761                 ns->nxstate = ns->op[ns->stateidx + 1];
 762                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
 763                                 idx, get_state_name(ns->state), get_state_name(ns->nxstate));
 764                 return 0;
 765         }
 766
 767         if (opsfound == 0) {
 768                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
 769                 if (ns->npstates != 0) {
 770                         NS_DBG("find_operation: no operation found, try again with state %s\n",
 771                                         get_state_name(ns->state));
 772                         ns->npstates = 0;
 773                         return find_operation(ns, 0);
 774
 775                 }
 776                 NS_DBG("find_operation: no operations found\n");
 777                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
 778                 return -2;
 779         }
 780
 781         if (flag) {
 782                 /* This shouldn't happen */
 783                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
 784                 return -2;
 785         }
 786
 787         NS_DBG("find_operation: there is still ambiguity\n");
 788
 789         ns->pstates[ns->npstates++] = ns->state;
 790
 791         return -1;
 792 }
 793
 794 /*
 795  * If state has any action bit, perform this action.
 796  *
 797  * RETURNS: 0 if success, -1 if error.
 798  */
 799 static int
 800 do_state_action(struct nandsim *ns, uint32_t action)
 801 {
 802         int i, num;
 803         int busdiv = ns->busw == 8 ? 1 : 2;
 804
 805         action &= ACTION_MASK;
 806
 807         /* Check that page address input is correct */
 808         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
 809                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
 810                 return -1;
 811         }
 812
 813         switch (action) {
 814
 815         case ACTION_CPY:
 816                 /*
 817                  * Copy page data to the internal buffer.
 818                  */
 819
 820                 /* Column shouldn't be very large */
 821                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
 822                         NS_ERR("do_state_action: column number is too large\n");
 823                         break;
 824                 }
 825                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
 826                 memcpy(ns->buf.byte, ns->mem.byte + NS_RAW_OFFSET(ns) + ns->regs.off, num);
 827
 828                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
 829                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
 830
 831                 if (ns->regs.off == 0)
 832                         NS_LOG("read page %d\n", ns->regs.row);
 833                 else if (ns->regs.off < ns->geom.pgsz)
 834                         NS_LOG("read page %d (second half)\n", ns->regs.row);
 835                 else
 836                         NS_LOG("read OOB of page %d\n", ns->regs.row);
 837
 838                 NS_UDELAY(access_delay);
 839                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
 840
 841                 break;
 842
 843         case ACTION_SECERASE:
 844                 /*
 845                  * Erase sector.
 846                  */
 847
 848                 if (ns->lines.wp) {
 849                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
 850                         return -1;
 851                 }
 852
 853                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
 854                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
 855                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
 856                         return -1;
 857                 }
 858
 859                 ns->regs.row = (ns->regs.row <<
 860                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
 861                 ns->regs.column = 0;
 862
 863                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
 864                                 ns->regs.row, NS_RAW_OFFSET(ns));
 865                 NS_LOG("erase sector %d\n", ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift));
 866
 867                 memset(ns->mem.byte + NS_RAW_OFFSET(ns), 0xFF, ns->geom.secszoob);
 868
 869                 NS_MDELAY(erase_delay);
 870
 871                 break;
 872
 873         case ACTION_PRGPAGE:
 874                 /*
 875                  * Programm page - move internal buffer data to the page.
 876                  */
 877
 878                 if (ns->lines.wp) {
 879                         NS_WARN("do_state_action: device is write-protected, programm\n");
 880                         return -1;
 881                 }
 882
 883                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
 884                 if (num != ns->regs.count) {
 885                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
 886                                         ns->regs.count, num);
 887                         return -1;
 888                 }
 889
 890                 for (i = 0; i < num; i++)
 891                         ns->mem.byte[NS_RAW_OFFSET(ns) + ns->regs.off + i] &= ns->buf.byte[i];
 892
 893                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
 894                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
 895                 NS_LOG("programm page %d\n", ns->regs.row);
 896
 897                 NS_UDELAY(programm_delay);
 898                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
 899
 900                 break;
 901
 902         case ACTION_ZEROOFF:
 903                 NS_DBG("do_state_action: set internal offset to 0\n");
 904                 ns->regs.off = 0;
 905                 break;
 906
 907         case ACTION_HALFOFF:
 908                 if (!(ns->options & OPT_PAGE512_8BIT)) {
 909                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
 910                                 "byte page size 8x chips\n");
 911                         return -1;
 912                 }
 913                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
 914                 ns->regs.off = ns->geom.pgsz/2;
 915                 break;
 916
 917         case ACTION_OOBOFF:
 918                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
 919                 ns->regs.off = ns->geom.pgsz;
 920                 break;
 921
 922         default:
 923                 NS_DBG("do_state_action: BUG! unknown action\n");
 924         }
 925
 926         return 0;
 927 }
 928
 929 /*
 930  * Switch simulator's state.
 931  */
 932 static void
 933 switch_state(struct nandsim *ns)
 934 {
 935         if (ns->op) {
 936                 /*
 937                  * The current operation have already been identified.
 938                  * Just follow the states chain.
 939                  */
 940
 941                 ns->stateidx += 1;
 942                 ns->state = ns->nxstate;
 943                 ns->nxstate = ns->op[ns->stateidx + 1];
 944
 945                 NS_DBG("switch_state: operation is known, switch to the next state, "
 946                         "state: %s, nxstate: %s\n",
 947                         get_state_name(ns->state), get_state_name(ns->nxstate));
 948
 949                 /* See, whether we need to do some action */
 950                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
 951                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
 952                         return;
 953                 }
 954
 955         } else {
 956                 /*
 957                  * We don't yet know which operation we perform.
 958                  * Try to identify it.
 959                  */
 960
 961                 /*
 962                  *  The only event causing the switch_state function to
 963                  *  be called with yet unknown operation is new command.
 964                  */
 965                 ns->state = get_state_by_command(ns->regs.command);
 966
 967                 NS_DBG("switch_state: operation is unknown, try to find it\n");
 968
 969                 if (find_operation(ns, 0) != 0)
 970                         return;
 971
 972                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
 973                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
 974                         return;
 975                 }
 976         }
 977
 978         /* For 16x devices column means the page offset in words */
 979         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
 980                 NS_DBG("switch_state: double the column number for 16x device\n");
 981                 ns->regs.column <<= 1;
 982         }
 983
 984         if (NS_STATE(ns->nxstate) == STATE_READY) {
 985                 /*
 986                  * The current state is the last. Return to STATE_READY
 987                  */
 988
 989                 u_char status = NS_STATUS_OK(ns);
 990
 991                 /* In case of data states, see if all bytes were input/output */
 992                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
 993                         && ns->regs.count != ns->regs.num) {
 994                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
 995                                         ns->regs.num - ns->regs.count);
 996                         status = NS_STATUS_FAILED(ns);
 997                 }
 998
 999                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1000
1001                 switch_to_ready_state(ns, status);
1002
1003                 return;
1004         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1005                 /*
1006                  * If the next state is data input/output, switch to it now
1007                  */
1008
1009                 ns->state      = ns->nxstate;
1010                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1011                 ns->regs.num   = ns->regs.count = 0;
1012
1013                 NS_DBG("switch_state: the next state is data I/O, switch, "
1014                         "state: %s, nxstate: %s\n",
1015                         get_state_name(ns->state), get_state_name(ns->nxstate));
1016
1017                 /*
1018                  * Set the internal register to the count of bytes which
1019                  * are expected to be input or output
1020                  */
1021                 switch (NS_STATE(ns->state)) {
1022                         case STATE_DATAIN:
1023                         case STATE_DATAOUT:
1024                                 ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1025                                 break;
1026
1027                         case STATE_DATAOUT_ID:
1028                                 ns->regs.num = ns->geom.idbytes;
1029                                 break;
1030
1031                         case STATE_DATAOUT_STATUS:
1032                         case STATE_DATAOUT_STATUS_M:
1033                                 ns->regs.count = ns->regs.num = 0;
1034                                 break;
1035
1036                         default:
1037                                 NS_ERR("switch_state: BUG! unknown data state\n");
1038                 }
1039
1040         } else if (ns->nxstate & STATE_ADDR_MASK) {
1041                 /*
1042                  * If the next state is address input, set the internal
1043                  * register to the number of expected address bytes
1044                  */
1045
1046                 ns->regs.count = 0;
1047
1048                 switch (NS_STATE(ns->nxstate)) {
1049                         case STATE_ADDR_PAGE:
1050                                 ns->regs.num = ns->geom.pgaddrbytes;
1051
1052                                 break;
1053                         case STATE_ADDR_SEC:
1054                                 ns->regs.num = ns->geom.secaddrbytes;
1055                                 break;
1056
1057                         case STATE_ADDR_ZERO:
1058                                 ns->regs.num = 1;
1059                                 break;
1060
1061                         default:
1062                                 NS_ERR("switch_state: BUG! unknown address state\n");
1063                 }
1064         } else {
1065                 /*
1066                  * Just reset internal counters.
1067                  */
1068
1069                 ns->regs.num = 0;
1070                 ns->regs.count = 0;
1071         }
1072 }
1073
1074 static void
1075 ns_hwcontrol(struct mtd_info *mtd, int cmd)
1076 {
1077         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1078
1079         switch (cmd) {
1080
1081         /* set CLE line high */
1082         case NAND_CTL_SETCLE:
1083                 NS_DBG("ns_hwcontrol: start command latch cycles\n");
1084                 ns->lines.cle  = 1;
1085                 break;
1086
1087         /* set CLE line low */
1088         case NAND_CTL_CLRCLE:
1089                 NS_DBG("ns_hwcontrol: stop command latch cycles\n");
1090                 ns->lines.cle  = 0;
1091                 break;
1092
1093         /* set ALE line high */
1094         case NAND_CTL_SETALE:
1095                 NS_DBG("ns_hwcontrol: start address latch cycles\n");
1096                 ns->lines.ale   = 1;
1097                 break;
1098
1099         /* set ALE line low */
1100         case NAND_CTL_CLRALE:
1101                 NS_DBG("ns_hwcontrol: stop address latch cycles\n");
1102                 ns->lines.ale  = 0;
1103                 break;
1104
1105         /* set WP line high */
1106         case NAND_CTL_SETWP:
1107                 NS_DBG("ns_hwcontrol: enable write protection\n");
1108                 ns->lines.wp = 1;
1109                 break;
1110
1111         /* set WP line low */
1112         case NAND_CTL_CLRWP:
1113                 NS_DBG("ns_hwcontrol: disable write protection\n");
1114                 ns->lines.wp = 0;
1115                 break;
1116
1117         /* set CE line low */
1118         case NAND_CTL_SETNCE:
1119                 NS_DBG("ns_hwcontrol: enable chip\n");
1120                 ns->lines.ce = 1;
1121                 break;
1122
1123         /* set CE line high */
1124         case NAND_CTL_CLRNCE:
1125                 NS_DBG("ns_hwcontrol: disable chip\n");
1126                 ns->lines.ce = 0;
1127                 break;
1128
1129         default:
1130                 NS_ERR("hwcontrol: unknown command\n");
1131         }
1132
1133         return;
1134 }
1135
1136 static u_char
1137 ns_nand_read_byte(struct mtd_info *mtd)
1138 {
1139         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1140         u_char outb = 0x00;
1141
1142         /* Sanity and correctness checks */
1143         if (!ns->lines.ce) {
1144                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1145                 return outb;
1146         }
1147         if (ns->lines.ale || ns->lines.cle) {
1148                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1149                 return outb;
1150         }
1151         if (!(ns->state & STATE_DATAOUT_MASK)) {
1152                 NS_WARN("read_byte: unexpected data output cycle, state is %s "
1153                         "return %#x\n", get_state_name(ns->state), (uint)outb);
1154                 return outb;
1155         }
1156
1157         /* Status register may be read as many times as it is wanted */
1158         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1159                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1160                 return ns->regs.status;
1161         }
1162
1163         /* Check if there is any data in the internal buffer which may be read */
1164         if (ns->regs.count == ns->regs.num) {
1165                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1166                 return outb;
1167         }
1168
1169         switch (NS_STATE(ns->state)) {
1170                 case STATE_DATAOUT:
1171                         if (ns->busw == 8) {
1172                                 outb = ns->buf.byte[ns->regs.count];
1173                                 ns->regs.count += 1;
1174                         } else {
1175                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1176                                 ns->regs.count += 2;
1177                         }
1178                         break;
1179                 case STATE_DATAOUT_ID:
1180                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1181                         outb = ns->ids[ns->regs.count];
1182                         ns->regs.count += 1;
1183                         break;
1184                 default:
1185                         BUG();
1186         }
1187
1188         if (ns->regs.count == ns->regs.num) {
1189                 NS_DBG("read_byte: all bytes were read\n");
1190
1191                 /*
1192                  * The OPT_AUTOINCR allows to read next conseqitive pages without
1193                  * new read operation cycle.
1194                  */
1195                 if ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT) {
1196                         ns->regs.count = 0;
1197                         if (ns->regs.row + 1 < ns->geom.pgnum)
1198                                 ns->regs.row += 1;
1199                         NS_DBG("read_byte: switch to the next page (%#x)\n", ns->regs.row);
1200                         do_state_action(ns, ACTION_CPY);
1201                 }
1202                 else if (NS_STATE(ns->nxstate) == STATE_READY)
1203                         switch_state(ns);
1204
1205         }
1206
1207         return outb;
1208 }
1209
1210 static void
1211 ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
1212 {
1213         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1214
1215         /* Sanity and correctness checks */
1216         if (!ns->lines.ce) {
1217                 NS_ERR("write_byte: chip is disabled, ignore write\n");
1218                 return;
1219         }
1220         if (ns->lines.ale && ns->lines.cle) {
1221                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1222                 return;
1223         }
1224
1225         if (ns->lines.cle == 1) {
1226                 /*
1227                  * The byte written is a command.
1228                  */
1229
1230                 if (byte == NAND_CMD_RESET) {
1231                         NS_LOG("reset chip\n");
1232                         switch_to_ready_state(ns, NS_STATUS_OK(ns));
1233                         return;
1234                 }
1235
1236                 /*
1237                  * Chip might still be in STATE_DATAOUT
1238                  * (if OPT_AUTOINCR feature is supported), STATE_DATAOUT_STATUS or
1239                  * STATE_DATAOUT_STATUS_M state. If so, switch state.
1240                  */
1241                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1242                         || NS_STATE(ns->state) == STATE_DATAOUT_STATUS_M
1243                         || ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT))
1244                         switch_state(ns);
1245
1246                 /* Check if chip is expecting command */
1247                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
1248                         /*
1249                          * We are in situation when something else (not command)
1250                          * was expected but command was input. In this case ignore
1251                          * previous command(s)/state(s) and accept the last one.
1252                          */
1253                         NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
1254                                 "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
1255                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1256                 }
1257
1258                 /* Check that the command byte is correct */
1259                 if (check_command(byte)) {
1260                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1261                         return;
1262                 }
1263
1264                 NS_DBG("command byte corresponding to %s state accepted\n",
1265                         get_state_name(get_state_by_command(byte)));
1266                 ns->regs.command = byte;
1267                 switch_state(ns);
1268
1269         } else if (ns->lines.ale == 1) {
1270                 /*
1271                  * The byte written is an address.
1272                  */
1273
1274                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
1275
1276                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
1277
1278                         if (find_operation(ns, 1) < 0)
1279                                 return;
1280
1281                         if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1282                                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1283                                 return;
1284                         }
1285
1286                         ns->regs.count = 0;
1287                         switch (NS_STATE(ns->nxstate)) {
1288                                 case STATE_ADDR_PAGE:
1289                                         ns->regs.num = ns->geom.pgaddrbytes;
1290                                         break;
1291                                 case STATE_ADDR_SEC:
1292                                         ns->regs.num = ns->geom.secaddrbytes;
1293                                         break;
1294                                 case STATE_ADDR_ZERO:
1295                                         ns->regs.num = 1;
1296                                         break;
1297                                 default:
1298                                         BUG();
1299                         }
1300                 }
1301
1302                 /* Check that chip is expecting address */
1303                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
1304                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
1305                                 "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
1306                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1307                         return;
1308                 }
1309
1310                 /* Check if this is expected byte */
1311                 if (ns->regs.count == ns->regs.num) {
1312                         NS_ERR("write_byte: no more address bytes expected\n");
1313                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1314                         return;
1315                 }
1316
1317                 accept_addr_byte(ns, byte);
1318
1319                 ns->regs.count += 1;
1320
1321                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
1322                                 (uint)byte, ns->regs.count, ns->regs.num);
1323
1324                 if (ns->regs.count == ns->regs.num) {
1325                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
1326                         switch_state(ns);
1327                 }
1328
1329         } else {
1330                 /*
1331                  * The byte written is an input data.
1332                  */
1333
1334                 /* Check that chip is expecting data input */
1335                 if (!(ns->state & STATE_DATAIN_MASK)) {
1336                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
1337                                 "switch to %s\n", (uint)byte,
1338                                 get_state_name(ns->state), get_state_name(STATE_READY));
1339                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1340                         return;
1341                 }
1342
1343                 /* Check if this is expected byte */
1344                 if (ns->regs.count == ns->regs.num) {
1345                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
1346                                         ns->regs.num);
1347                         return;
1348                 }
1349
1350                 if (ns->busw == 8) {
1351                         ns->buf.byte[ns->regs.count] = byte;
1352                         ns->regs.count += 1;
1353                 } else {
1354                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
1355                         ns->regs.count += 2;
1356                 }
1357         }
1358
1359         return;
1360 }
1361
1362 static int
1363 ns_device_ready(struct mtd_info *mtd)
1364 {
1365         NS_DBG("device_ready\n");
1366         return 1;
1367 }
1368
1369 static uint16_t
1370 ns_nand_read_word(struct mtd_info *mtd)
1371 {
1372         struct nand_chip *chip = (struct nand_chip *)mtd->priv;
1373
1374         NS_DBG("read_word\n");
1375
1376         return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
1377 }
1378
1379 static void
1380 ns_nand_write_word(struct mtd_info *mtd, uint16_t word)
1381 {
1382         struct nand_chip *chip = (struct nand_chip *)mtd->priv;
1383
1384         NS_DBG("write_word\n");
1385
1386         chip->write_byte(mtd, word & 0xFF);
1387         chip->write_byte(mtd, word >> 8);
1388 }
1389
1390 static void
1391 ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
1392 {
1393         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1394
1395         /* Check that chip is expecting data input */
1396         if (!(ns->state & STATE_DATAIN_MASK)) {
1397                 NS_ERR("write_buf: data input isn't expected, state is %s, "
1398                         "switch to STATE_READY\n", get_state_name(ns->state));
1399                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1400                 return;
1401         }
1402
1403         /* Check if these are expected bytes */
1404         if (ns->regs.count + len > ns->regs.num) {
1405                 NS_ERR("write_buf: too many input bytes\n");
1406                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1407                 return;
1408         }
1409
1410         memcpy(ns->buf.byte + ns->regs.count, buf, len);
1411         ns->regs.count += len;
1412
1413         if (ns->regs.count == ns->regs.num) {
1414                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
1415         }
1416 }
1417
1418 static void
1419 ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
1420 {
1421         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1422
1423         /* Sanity and correctness checks */
1424         if (!ns->lines.ce) {
1425                 NS_ERR("read_buf: chip is disabled\n");
1426                 return;
1427         }
1428         if (ns->lines.ale || ns->lines.cle) {
1429                 NS_ERR("read_buf: ALE or CLE pin is high\n");
1430                 return;
1431         }
1432         if (!(ns->state & STATE_DATAOUT_MASK)) {
1433                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
1434                         get_state_name(ns->state));
1435                 return;
1436         }
1437
1438         if (NS_STATE(ns->state) != STATE_DATAOUT) {
1439                 int i;
1440
1441                 for (i = 0; i < len; i++)
1442                         buf[i] = ((struct nand_chip *)mtd->priv)->read_byte(mtd);
1443
1444                 return;
1445         }
1446
1447         /* Check if these are expected bytes */
1448         if (ns->regs.count + len > ns->regs.num) {
1449                 NS_ERR("read_buf: too many bytes to read\n");
1450                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1451                 return;
1452         }
1453
1454         memcpy(buf, ns->buf.byte + ns->regs.count, len);
1455         ns->regs.count += len;
1456
1457         if (ns->regs.count == ns->regs.num) {
1458                 if ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT) {
1459                         ns->regs.count = 0;
1460                         if (ns->regs.row + 1 < ns->geom.pgnum)
1461                                 ns->regs.row += 1;
1462                         NS_DBG("read_buf: switch to the next page (%#x)\n", ns->regs.row);
1463                         do_state_action(ns, ACTION_CPY);
1464                 }
1465                 else if (NS_STATE(ns->nxstate) == STATE_READY)
1466                         switch_state(ns);
1467         }
1468
1469         return;
1470 }
1471
1472 static int
1473 ns_nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
1474 {
1475         ns_nand_read_buf(mtd, (u_char *)&ns_verify_buf[0], len);
1476
1477         if (!memcmp(buf, &ns_verify_buf[0], len)) {
1478                 NS_DBG("verify_buf: the buffer is OK\n");
1479                 return 0;
1480         } else {
1481                 NS_DBG("verify_buf: the buffer is wrong\n");
1482                 return -EFAULT;
1483         }
1484 }
1485
1486 /*
1487  * Module initialization function
1488  */
1489 int __init ns_init_module(void)
1490 {
1491         struct nand_chip *chip;
1492         struct nandsim *nand;
1493         int retval = -ENOMEM;
1494
1495         if (bus_width != 8 && bus_width != 16) {
1496                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
1497                 return -EINVAL;
1498         }
1499
1500         /* Allocate and initialize mtd_info, nand_chip and nandsim structures */
1501         nsmtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip)
1502                                 + sizeof(struct nandsim), GFP_KERNEL);
1503         if (!nsmtd) {
1504                 NS_ERR("unable to allocate core structures.\n");
1505                 return -ENOMEM;
1506         }
1507         memset(nsmtd, 0, sizeof(struct mtd_info) + sizeof(struct nand_chip) +
1508                         sizeof(struct nandsim));
1509         chip        = (struct nand_chip *)(nsmtd + 1);
1510         nsmtd->priv = (void *)chip;
1511         nand        = (struct nandsim *)(chip + 1);
1512         chip->priv  = (void *)nand;
1513
1514         /*
1515          * Register simulator's callbacks.
1516          */
1517         chip->hwcontrol  = ns_hwcontrol;
1518         chip->read_byte  = ns_nand_read_byte;
1519         chip->dev_ready  = ns_device_ready;
1520         chip->write_byte = ns_nand_write_byte;
1521         chip->write_buf  = ns_nand_write_buf;
1522         chip->read_buf   = ns_nand_read_buf;
1523         chip->verify_buf = ns_nand_verify_buf;
1524         chip->write_word = ns_nand_write_word;
1525         chip->read_word  = ns_nand_read_word;
1526         chip->eccmode    = NAND_ECC_SOFT;
1527         chip->options   |= NAND_SKIP_BBTSCAN;
1528
1529         /*
1530          * Perform minimum nandsim structure initialization to handle
1531          * the initial ID read command correctly
1532          */
1533         if (third_id_byte != 0xFF || fourth_id_byte != 0xFF)
1534                 nand->geom.idbytes = 4;
1535         else
1536                 nand->geom.idbytes = 2;
1537         nand->regs.status = NS_STATUS_OK(nand);
1538         nand->nxstate = STATE_UNKNOWN;
1539         nand->options |= OPT_PAGE256; /* temporary value */
1540         nand->ids[0] = first_id_byte;
1541         nand->ids[1] = second_id_byte;
1542         nand->ids[2] = third_id_byte;
1543         nand->ids[3] = fourth_id_byte;
1544         if (bus_width == 16) {
1545                 nand->busw = 16;
1546                 chip->options |= NAND_BUSWIDTH_16;
1547         }
1548
1549         if ((retval = nand_scan(nsmtd, 1)) != 0) {
1550                 NS_ERR("can't register NAND Simulator\n");
1551                 if (retval > 0)
1552                         retval = -ENXIO;
1553                 goto error;
1554         }
1555
1556         if ((retval = init_nandsim(nsmtd)) != 0) {
1557                 NS_ERR("scan_bbt: can't initialize the nandsim structure\n");
1558                 goto error;
1559         }
1560
1561         if ((retval = nand_default_bbt(nsmtd)) != 0) {
1562                 free_nandsim(nand);
1563                 goto error;
1564         }
1565
1566         /* Register NAND as one big partition */
1567         add_mtd_partitions(nsmtd, &nand->part, 1);
1568
1569         return 0;
1570
1571 error:
1572         kfree(nsmtd);
1573
1574         return retval;
1575 }
1576
1577 module_init(ns_init_module);
1578
1579 /*
1580  * Module clean-up function
1581  */
1582 static void __exit ns_cleanup_module(void)
1583 {
1584         struct nandsim *ns = (struct nandsim *)(((struct nand_chip *)nsmtd->priv)->priv);
1585
1586         free_nandsim(ns);    /* Free nandsim private resources */
1587         nand_release(nsmtd); /* Unregisterd drived */
1588         kfree(nsmtd);        /* Free other structures */
1589 }
1590
1591 module_exit(ns_cleanup_module);
1592
1593 MODULE_LICENSE ("GPL");
1594 MODULE_AUTHOR ("Artem B. Bityuckiy");
1595 MODULE_DESCRIPTION ("The NAND flash simulator");
1596