Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6] / 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/init.h>
29 #include <linux/types.h>
30 #include <linux/module.h>
31 #include <linux/moduleparam.h>
32 #include <linux/vmalloc.h>
33 #include <linux/slab.h>
34 #include <linux/errno.h>
35 #include <linux/string.h>
36 #include <linux/mtd/mtd.h>
37 #include <linux/mtd/nand.h>
38 #include <linux/mtd/partitions.h>
39 #include <linux/delay.h>
40 #include <linux/list.h>
41 #include <linux/random.h>
42
43 /* Default simulator parameters values */
44 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
45     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
46     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
47     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
48 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
49 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
50 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
51 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
52 #endif
53
54 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
55 #define CONFIG_NANDSIM_ACCESS_DELAY 25
56 #endif
57 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
58 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
59 #endif
60 #ifndef CONFIG_NANDSIM_ERASE_DELAY
61 #define CONFIG_NANDSIM_ERASE_DELAY 2
62 #endif
63 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
64 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
65 #endif
66 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
67 #define CONFIG_NANDSIM_INPUT_CYCLE  50
68 #endif
69 #ifndef CONFIG_NANDSIM_BUS_WIDTH
70 #define CONFIG_NANDSIM_BUS_WIDTH  8
71 #endif
72 #ifndef CONFIG_NANDSIM_DO_DELAYS
73 #define CONFIG_NANDSIM_DO_DELAYS  0
74 #endif
75 #ifndef CONFIG_NANDSIM_LOG
76 #define CONFIG_NANDSIM_LOG        0
77 #endif
78 #ifndef CONFIG_NANDSIM_DBG
79 #define CONFIG_NANDSIM_DBG        0
80 #endif
81
82 static uint first_id_byte  = CONFIG_NANDSIM_FIRST_ID_BYTE;
83 static uint second_id_byte = CONFIG_NANDSIM_SECOND_ID_BYTE;
84 static uint third_id_byte  = CONFIG_NANDSIM_THIRD_ID_BYTE;
85 static uint fourth_id_byte = CONFIG_NANDSIM_FOURTH_ID_BYTE;
86 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
87 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
88 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
89 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
90 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
91 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
92 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
93 static uint log            = CONFIG_NANDSIM_LOG;
94 static uint dbg            = CONFIG_NANDSIM_DBG;
95 static unsigned long parts[MAX_MTD_DEVICES];
96 static unsigned int parts_num;
97 static char *badblocks = NULL;
98 static char *weakblocks = NULL;
99 static char *weakpages = NULL;
100 static unsigned int bitflips = 0;
101 static char *gravepages = NULL;
102 static unsigned int rptwear = 0;
103 static unsigned int overridesize = 0;
104
105 module_param(first_id_byte,  uint, 0400);
106 module_param(second_id_byte, uint, 0400);
107 module_param(third_id_byte,  uint, 0400);
108 module_param(fourth_id_byte, uint, 0400);
109 module_param(access_delay,   uint, 0400);
110 module_param(programm_delay, uint, 0400);
111 module_param(erase_delay,    uint, 0400);
112 module_param(output_cycle,   uint, 0400);
113 module_param(input_cycle,    uint, 0400);
114 module_param(bus_width,      uint, 0400);
115 module_param(do_delays,      uint, 0400);
116 module_param(log,            uint, 0400);
117 module_param(dbg,            uint, 0400);
118 module_param_array(parts, ulong, &parts_num, 0400);
119 module_param(badblocks,      charp, 0400);
120 module_param(weakblocks,     charp, 0400);
121 module_param(weakpages,      charp, 0400);
122 module_param(bitflips,       uint, 0400);
123 module_param(gravepages,     charp, 0400);
124 module_param(rptwear,        uint, 0400);
125 module_param(overridesize,   uint, 0400);
126
127 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID)");
128 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID)");
129 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command");
130 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command");
131 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microiseconds)");
132 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
133 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
134 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanodeconds)");
135 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanodeconds)");
136 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
137 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
138 MODULE_PARM_DESC(log,            "Perform logging if not zero");
139 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
140 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
141 /* Page and erase block positions for the following parameters are independent of any partitions */
142 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
143 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
144                                  " separated by commas e.g. 113:2 means eb 113"
145                                  " can be erased only twice before failing");
146 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
147                                  " separated by commas e.g. 1401:2 means page 1401"
148                                  " can be written only twice before failing");
149 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
150 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
151                                  " separated by commas e.g. 1401:2 means page 1401"
152                                  " can be read only twice before failing");
153 MODULE_PARM_DESC(rptwear,        "Number of erases inbetween reporting wear, if not zero");
154 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
155                                  "The size is specified in erase blocks and as the exponent of a power of two"
156                                  " e.g. 5 means a size of 32 erase blocks");
157
158 /* The largest possible page size */
159 #define NS_LARGEST_PAGE_SIZE    2048
160
161 /* The prefix for simulator output */
162 #define NS_OUTPUT_PREFIX "[nandsim]"
163
164 /* Simulator's output macros (logging, debugging, warning, error) */
165 #define NS_LOG(args...) \
166         do { if (log) printk(KERN_DEBUG NS_OUTPUT_PREFIX " log: " args); } while(0)
167 #define NS_DBG(args...) \
168         do { if (dbg) printk(KERN_DEBUG NS_OUTPUT_PREFIX " debug: " args); } while(0)
169 #define NS_WARN(args...) \
170         do { printk(KERN_WARNING NS_OUTPUT_PREFIX " warning: " args); } while(0)
171 #define NS_ERR(args...) \
172         do { printk(KERN_ERR NS_OUTPUT_PREFIX " error: " args); } while(0)
173 #define NS_INFO(args...) \
174         do { printk(KERN_INFO NS_OUTPUT_PREFIX " " args); } while(0)
175
176 /* Busy-wait delay macros (microseconds, milliseconds) */
177 #define NS_UDELAY(us) \
178         do { if (do_delays) udelay(us); } while(0)
179 #define NS_MDELAY(us) \
180         do { if (do_delays) mdelay(us); } while(0)
181
182 /* Is the nandsim structure initialized ? */
183 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
184
185 /* Good operation completion status */
186 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
187
188 /* Operation failed completion status */
189 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
190
191 /* Calculate the page offset in flash RAM image by (row, column) address */
192 #define NS_RAW_OFFSET(ns) \
193         (((ns)->regs.row << (ns)->geom.pgshift) + ((ns)->regs.row * (ns)->geom.oobsz) + (ns)->regs.column)
194
195 /* Calculate the OOB offset in flash RAM image by (row, column) address */
196 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
197
198 /* After a command is input, the simulator goes to one of the following states */
199 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
200 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
201 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
202 #define STATE_CMD_PAGEPROG     0x00000004 /* start page programm */
203 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
204 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
205 #define STATE_CMD_STATUS       0x00000007 /* read status */
206 #define STATE_CMD_STATUS_M     0x00000008 /* read multi-plane status (isn't implemented) */
207 #define STATE_CMD_SEQIN        0x00000009 /* sequential data imput */
208 #define STATE_CMD_READID       0x0000000A /* read ID */
209 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
210 #define STATE_CMD_RESET        0x0000000C /* reset */
211 #define STATE_CMD_MASK         0x0000000F /* command states mask */
212
213 /* After an addres is input, the simulator goes to one of these states */
214 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
215 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
216 #define STATE_ADDR_ZERO        0x00000030 /* one byte zero address was accepted */
217 #define STATE_ADDR_MASK        0x00000030 /* address states mask */
218
219 /* Durind data input/output the simulator is in these states */
220 #define STATE_DATAIN           0x00000100 /* waiting for data input */
221 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
222
223 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
224 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
225 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
226 #define STATE_DATAOUT_STATUS_M 0x00004000 /* waiting for multi-plane status output */
227 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
228
229 /* Previous operation is done, ready to accept new requests */
230 #define STATE_READY            0x00000000
231
232 /* This state is used to mark that the next state isn't known yet */
233 #define STATE_UNKNOWN          0x10000000
234
235 /* Simulator's actions bit masks */
236 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
237 #define ACTION_PRGPAGE   0x00200000 /* programm the internal buffer to flash */
238 #define ACTION_SECERASE  0x00300000 /* erase sector */
239 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
240 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
241 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
242 #define ACTION_MASK      0x00700000 /* action mask */
243
244 #define NS_OPER_NUM      12 /* Number of operations supported by the simulator */
245 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
246
247 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
248 #define OPT_PAGE256      0x00000001 /* 256-byte  page chips */
249 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
250 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
251 #define OPT_SMARTMEDIA   0x00000010 /* SmartMedia technology chips */
252 #define OPT_AUTOINCR     0x00000020 /* page number auto inctimentation is possible */
253 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
254 #define OPT_LARGEPAGE    (OPT_PAGE2048) /* 2048-byte page chips */
255 #define OPT_SMALLPAGE    (OPT_PAGE256  | OPT_PAGE512)  /* 256 and 512-byte page chips */
256
257 /* Remove action bits ftom state */
258 #define NS_STATE(x) ((x) & ~ACTION_MASK)
259
260 /*
261  * Maximum previous states which need to be saved. Currently saving is
262  * only needed for page programm operation with preceeded read command
263  * (which is only valid for 512-byte pages).
264  */
265 #define NS_MAX_PREVSTATES 1
266
267 /*
268  * A union to represent flash memory contents and flash buffer.
269  */
270 union ns_mem {
271         u_char *byte;    /* for byte access */
272         uint16_t *word;  /* for 16-bit word access */
273 };
274
275 /*
276  * The structure which describes all the internal simulator data.
277  */
278 struct nandsim {
279         struct mtd_partition partitions[MAX_MTD_DEVICES];
280         unsigned int nbparts;
281
282         uint busw;              /* flash chip bus width (8 or 16) */
283         u_char ids[4];          /* chip's ID bytes */
284         uint32_t options;       /* chip's characteristic bits */
285         uint32_t state;         /* current chip state */
286         uint32_t nxstate;       /* next expected state */
287
288         uint32_t *op;           /* current operation, NULL operations isn't known yet  */
289         uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
290         uint16_t npstates;      /* number of previous states saved */
291         uint16_t stateidx;      /* current state index */
292
293         /* The simulated NAND flash pages array */
294         union ns_mem *pages;
295
296         /* Internal buffer of page + OOB size bytes */
297         union ns_mem buf;
298
299         /* NAND flash "geometry" */
300         struct nandsin_geometry {
301                 uint32_t totsz;     /* total flash size, bytes */
302                 uint32_t secsz;     /* flash sector (erase block) size, bytes */
303                 uint pgsz;          /* NAND flash page size, bytes */
304                 uint oobsz;         /* page OOB area size, bytes */
305                 uint32_t totszoob;  /* total flash size including OOB, bytes */
306                 uint pgszoob;       /* page size including OOB , bytes*/
307                 uint secszoob;      /* sector size including OOB, bytes */
308                 uint pgnum;         /* total number of pages */
309                 uint pgsec;         /* number of pages per sector */
310                 uint secshift;      /* bits number in sector size */
311                 uint pgshift;       /* bits number in page size */
312                 uint oobshift;      /* bits number in OOB size */
313                 uint pgaddrbytes;   /* bytes per page address */
314                 uint secaddrbytes;  /* bytes per sector address */
315                 uint idbytes;       /* the number ID bytes that this chip outputs */
316         } geom;
317
318         /* NAND flash internal registers */
319         struct nandsim_regs {
320                 unsigned command; /* the command register */
321                 u_char   status;  /* the status register */
322                 uint     row;     /* the page number */
323                 uint     column;  /* the offset within page */
324                 uint     count;   /* internal counter */
325                 uint     num;     /* number of bytes which must be processed */
326                 uint     off;     /* fixed page offset */
327         } regs;
328
329         /* NAND flash lines state */
330         struct ns_lines_status {
331                 int ce;  /* chip Enable */
332                 int cle; /* command Latch Enable */
333                 int ale; /* address Latch Enable */
334                 int wp;  /* write Protect */
335         } lines;
336 };
337
338 /*
339  * Operations array. To perform any operation the simulator must pass
340  * through the correspondent states chain.
341  */
342 static struct nandsim_operations {
343         uint32_t reqopts;  /* options which are required to perform the operation */
344         uint32_t states[NS_OPER_STATES]; /* operation's states */
345 } ops[NS_OPER_NUM] = {
346         /* Read page + OOB from the beginning */
347         {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
348                         STATE_DATAOUT, STATE_READY}},
349         /* Read page + OOB from the second half */
350         {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
351                         STATE_DATAOUT, STATE_READY}},
352         /* Read OOB */
353         {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
354                         STATE_DATAOUT, STATE_READY}},
355         /* Programm page starting from the beginning */
356         {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
357                         STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
358         /* Programm page starting from the beginning */
359         {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
360                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
361         /* Programm page starting from the second half */
362         {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
363                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
364         /* Programm OOB */
365         {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
366                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
367         /* Erase sector */
368         {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
369         /* Read status */
370         {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
371         /* Read multi-plane status */
372         {OPT_SMARTMEDIA, {STATE_CMD_STATUS_M, STATE_DATAOUT_STATUS_M, STATE_READY}},
373         /* Read ID */
374         {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
375         /* Large page devices read page */
376         {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
377                                STATE_DATAOUT, STATE_READY}}
378 };
379
380 struct weak_block {
381         struct list_head list;
382         unsigned int erase_block_no;
383         unsigned int max_erases;
384         unsigned int erases_done;
385 };
386
387 static LIST_HEAD(weak_blocks);
388
389 struct weak_page {
390         struct list_head list;
391         unsigned int page_no;
392         unsigned int max_writes;
393         unsigned int writes_done;
394 };
395
396 static LIST_HEAD(weak_pages);
397
398 struct grave_page {
399         struct list_head list;
400         unsigned int page_no;
401         unsigned int max_reads;
402         unsigned int reads_done;
403 };
404
405 static LIST_HEAD(grave_pages);
406
407 static unsigned long *erase_block_wear = NULL;
408 static unsigned int wear_eb_count = 0;
409 static unsigned long total_wear = 0;
410 static unsigned int rptwear_cnt = 0;
411
412 /* MTD structure for NAND controller */
413 static struct mtd_info *nsmtd;
414
415 static u_char ns_verify_buf[NS_LARGEST_PAGE_SIZE];
416
417 /*
418  * Allocate array of page pointers and initialize the array to NULL
419  * pointers.
420  *
421  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
422  */
423 static int alloc_device(struct nandsim *ns)
424 {
425         int i;
426
427         ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem));
428         if (!ns->pages) {
429                 NS_ERR("alloc_map: unable to allocate page array\n");
430                 return -ENOMEM;
431         }
432         for (i = 0; i < ns->geom.pgnum; i++) {
433                 ns->pages[i].byte = NULL;
434         }
435
436         return 0;
437 }
438
439 /*
440  * Free any allocated pages, and free the array of page pointers.
441  */
442 static void free_device(struct nandsim *ns)
443 {
444         int i;
445
446         if (ns->pages) {
447                 for (i = 0; i < ns->geom.pgnum; i++) {
448                         if (ns->pages[i].byte)
449                                 kfree(ns->pages[i].byte);
450                 }
451                 vfree(ns->pages);
452         }
453 }
454
455 static char *get_partition_name(int i)
456 {
457         char buf[64];
458         sprintf(buf, "NAND simulator partition %d", i);
459         return kstrdup(buf, GFP_KERNEL);
460 }
461
462 /*
463  * Initialize the nandsim structure.
464  *
465  * RETURNS: 0 if success, -ERRNO if failure.
466  */
467 static int init_nandsim(struct mtd_info *mtd)
468 {
469         struct nand_chip *chip = (struct nand_chip *)mtd->priv;
470         struct nandsim   *ns   = (struct nandsim *)(chip->priv);
471         int i, ret = 0;
472         u_int32_t remains;
473         u_int32_t next_offset;
474
475         if (NS_IS_INITIALIZED(ns)) {
476                 NS_ERR("init_nandsim: nandsim is already initialized\n");
477                 return -EIO;
478         }
479
480         /* Force mtd to not do delays */
481         chip->chip_delay = 0;
482
483         /* Initialize the NAND flash parameters */
484         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
485         ns->geom.totsz    = mtd->size;
486         ns->geom.pgsz     = mtd->writesize;
487         ns->geom.oobsz    = mtd->oobsize;
488         ns->geom.secsz    = mtd->erasesize;
489         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
490         ns->geom.pgnum    = ns->geom.totsz / ns->geom.pgsz;
491         ns->geom.totszoob = ns->geom.totsz + ns->geom.pgnum * ns->geom.oobsz;
492         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
493         ns->geom.pgshift  = chip->page_shift;
494         ns->geom.oobshift = ffs(ns->geom.oobsz) - 1;
495         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
496         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
497         ns->options = 0;
498
499         if (ns->geom.pgsz == 256) {
500                 ns->options |= OPT_PAGE256;
501         }
502         else if (ns->geom.pgsz == 512) {
503                 ns->options |= (OPT_PAGE512 | OPT_AUTOINCR);
504                 if (ns->busw == 8)
505                         ns->options |= OPT_PAGE512_8BIT;
506         } else if (ns->geom.pgsz == 2048) {
507                 ns->options |= OPT_PAGE2048;
508         } else {
509                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
510                 return -EIO;
511         }
512
513         if (ns->options & OPT_SMALLPAGE) {
514                 if (ns->geom.totsz < (64 << 20)) {
515                         ns->geom.pgaddrbytes  = 3;
516                         ns->geom.secaddrbytes = 2;
517                 } else {
518                         ns->geom.pgaddrbytes  = 4;
519                         ns->geom.secaddrbytes = 3;
520                 }
521         } else {
522                 if (ns->geom.totsz <= (128 << 20)) {
523                         ns->geom.pgaddrbytes  = 4;
524                         ns->geom.secaddrbytes = 2;
525                 } else {
526                         ns->geom.pgaddrbytes  = 5;
527                         ns->geom.secaddrbytes = 3;
528                 }
529         }
530
531         /* Fill the partition_info structure */
532         if (parts_num > ARRAY_SIZE(ns->partitions)) {
533                 NS_ERR("too many partitions.\n");
534                 ret = -EINVAL;
535                 goto error;
536         }
537         remains = ns->geom.totsz;
538         next_offset = 0;
539         for (i = 0; i < parts_num; ++i) {
540                 unsigned long part = parts[i];
541                 if (!part || part > remains / ns->geom.secsz) {
542                         NS_ERR("bad partition size.\n");
543                         ret = -EINVAL;
544                         goto error;
545                 }
546                 ns->partitions[i].name   = get_partition_name(i);
547                 ns->partitions[i].offset = next_offset;
548                 ns->partitions[i].size   = part * ns->geom.secsz;
549                 next_offset += ns->partitions[i].size;
550                 remains -= ns->partitions[i].size;
551         }
552         ns->nbparts = parts_num;
553         if (remains) {
554                 if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
555                         NS_ERR("too many partitions.\n");
556                         ret = -EINVAL;
557                         goto error;
558                 }
559                 ns->partitions[i].name   = get_partition_name(i);
560                 ns->partitions[i].offset = next_offset;
561                 ns->partitions[i].size   = remains;
562                 ns->nbparts += 1;
563         }
564
565         /* Detect how many ID bytes the NAND chip outputs */
566         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
567                 if (second_id_byte != nand_flash_ids[i].id)
568                         continue;
569                 if (!(nand_flash_ids[i].options & NAND_NO_AUTOINCR))
570                         ns->options |= OPT_AUTOINCR;
571         }
572
573         if (ns->busw == 16)
574                 NS_WARN("16-bit flashes support wasn't tested\n");
575
576         printk("flash size: %u MiB\n",          ns->geom.totsz >> 20);
577         printk("page size: %u bytes\n",         ns->geom.pgsz);
578         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
579         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
580         printk("pages number: %u\n",            ns->geom.pgnum);
581         printk("pages per sector: %u\n",        ns->geom.pgsec);
582         printk("bus width: %u\n",               ns->busw);
583         printk("bits in sector size: %u\n",     ns->geom.secshift);
584         printk("bits in page size: %u\n",       ns->geom.pgshift);
585         printk("bits in OOB size: %u\n",        ns->geom.oobshift);
586         printk("flash size with OOB: %u KiB\n", ns->geom.totszoob >> 10);
587         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
588         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
589         printk("options: %#x\n",                ns->options);
590
591         if ((ret = alloc_device(ns)) != 0)
592                 goto error;
593
594         /* Allocate / initialize the internal buffer */
595         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
596         if (!ns->buf.byte) {
597                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
598                         ns->geom.pgszoob);
599                 ret = -ENOMEM;
600                 goto error;
601         }
602         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
603
604         return 0;
605
606 error:
607         free_device(ns);
608
609         return ret;
610 }
611
612 /*
613  * Free the nandsim structure.
614  */
615 static void free_nandsim(struct nandsim *ns)
616 {
617         kfree(ns->buf.byte);
618         free_device(ns);
619
620         return;
621 }
622
623 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
624 {
625         char *w;
626         int zero_ok;
627         unsigned int erase_block_no;
628         loff_t offset;
629
630         if (!badblocks)
631                 return 0;
632         w = badblocks;
633         do {
634                 zero_ok = (*w == '0' ? 1 : 0);
635                 erase_block_no = simple_strtoul(w, &w, 0);
636                 if (!zero_ok && !erase_block_no) {
637                         NS_ERR("invalid badblocks.\n");
638                         return -EINVAL;
639                 }
640                 offset = erase_block_no * ns->geom.secsz;
641                 if (mtd->block_markbad(mtd, offset)) {
642                         NS_ERR("invalid badblocks.\n");
643                         return -EINVAL;
644                 }
645                 if (*w == ',')
646                         w += 1;
647         } while (*w);
648         return 0;
649 }
650
651 static int parse_weakblocks(void)
652 {
653         char *w;
654         int zero_ok;
655         unsigned int erase_block_no;
656         unsigned int max_erases;
657         struct weak_block *wb;
658
659         if (!weakblocks)
660                 return 0;
661         w = weakblocks;
662         do {
663                 zero_ok = (*w == '0' ? 1 : 0);
664                 erase_block_no = simple_strtoul(w, &w, 0);
665                 if (!zero_ok && !erase_block_no) {
666                         NS_ERR("invalid weakblocks.\n");
667                         return -EINVAL;
668                 }
669                 max_erases = 3;
670                 if (*w == ':') {
671                         w += 1;
672                         max_erases = simple_strtoul(w, &w, 0);
673                 }
674                 if (*w == ',')
675                         w += 1;
676                 wb = kzalloc(sizeof(*wb), GFP_KERNEL);
677                 if (!wb) {
678                         NS_ERR("unable to allocate memory.\n");
679                         return -ENOMEM;
680                 }
681                 wb->erase_block_no = erase_block_no;
682                 wb->max_erases = max_erases;
683                 list_add(&wb->list, &weak_blocks);
684         } while (*w);
685         return 0;
686 }
687
688 static int erase_error(unsigned int erase_block_no)
689 {
690         struct weak_block *wb;
691
692         list_for_each_entry(wb, &weak_blocks, list)
693                 if (wb->erase_block_no == erase_block_no) {
694                         if (wb->erases_done >= wb->max_erases)
695                                 return 1;
696                         wb->erases_done += 1;
697                         return 0;
698                 }
699         return 0;
700 }
701
702 static int parse_weakpages(void)
703 {
704         char *w;
705         int zero_ok;
706         unsigned int page_no;
707         unsigned int max_writes;
708         struct weak_page *wp;
709
710         if (!weakpages)
711                 return 0;
712         w = weakpages;
713         do {
714                 zero_ok = (*w == '0' ? 1 : 0);
715                 page_no = simple_strtoul(w, &w, 0);
716                 if (!zero_ok && !page_no) {
717                         NS_ERR("invalid weakpagess.\n");
718                         return -EINVAL;
719                 }
720                 max_writes = 3;
721                 if (*w == ':') {
722                         w += 1;
723                         max_writes = simple_strtoul(w, &w, 0);
724                 }
725                 if (*w == ',')
726                         w += 1;
727                 wp = kzalloc(sizeof(*wp), GFP_KERNEL);
728                 if (!wp) {
729                         NS_ERR("unable to allocate memory.\n");
730                         return -ENOMEM;
731                 }
732                 wp->page_no = page_no;
733                 wp->max_writes = max_writes;
734                 list_add(&wp->list, &weak_pages);
735         } while (*w);
736         return 0;
737 }
738
739 static int write_error(unsigned int page_no)
740 {
741         struct weak_page *wp;
742
743         list_for_each_entry(wp, &weak_pages, list)
744                 if (wp->page_no == page_no) {
745                         if (wp->writes_done >= wp->max_writes)
746                                 return 1;
747                         wp->writes_done += 1;
748                         return 0;
749                 }
750         return 0;
751 }
752
753 static int parse_gravepages(void)
754 {
755         char *g;
756         int zero_ok;
757         unsigned int page_no;
758         unsigned int max_reads;
759         struct grave_page *gp;
760
761         if (!gravepages)
762                 return 0;
763         g = gravepages;
764         do {
765                 zero_ok = (*g == '0' ? 1 : 0);
766                 page_no = simple_strtoul(g, &g, 0);
767                 if (!zero_ok && !page_no) {
768                         NS_ERR("invalid gravepagess.\n");
769                         return -EINVAL;
770                 }
771                 max_reads = 3;
772                 if (*g == ':') {
773                         g += 1;
774                         max_reads = simple_strtoul(g, &g, 0);
775                 }
776                 if (*g == ',')
777                         g += 1;
778                 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
779                 if (!gp) {
780                         NS_ERR("unable to allocate memory.\n");
781                         return -ENOMEM;
782                 }
783                 gp->page_no = page_no;
784                 gp->max_reads = max_reads;
785                 list_add(&gp->list, &grave_pages);
786         } while (*g);
787         return 0;
788 }
789
790 static int read_error(unsigned int page_no)
791 {
792         struct grave_page *gp;
793
794         list_for_each_entry(gp, &grave_pages, list)
795                 if (gp->page_no == page_no) {
796                         if (gp->reads_done >= gp->max_reads)
797                                 return 1;
798                         gp->reads_done += 1;
799                         return 0;
800                 }
801         return 0;
802 }
803
804 static void free_lists(void)
805 {
806         struct list_head *pos, *n;
807         list_for_each_safe(pos, n, &weak_blocks) {
808                 list_del(pos);
809                 kfree(list_entry(pos, struct weak_block, list));
810         }
811         list_for_each_safe(pos, n, &weak_pages) {
812                 list_del(pos);
813                 kfree(list_entry(pos, struct weak_page, list));
814         }
815         list_for_each_safe(pos, n, &grave_pages) {
816                 list_del(pos);
817                 kfree(list_entry(pos, struct grave_page, list));
818         }
819         kfree(erase_block_wear);
820 }
821
822 static int setup_wear_reporting(struct mtd_info *mtd)
823 {
824         size_t mem;
825
826         if (!rptwear)
827                 return 0;
828         wear_eb_count = mtd->size / mtd->erasesize;
829         mem = wear_eb_count * sizeof(unsigned long);
830         if (mem / sizeof(unsigned long) != wear_eb_count) {
831                 NS_ERR("Too many erase blocks for wear reporting\n");
832                 return -ENOMEM;
833         }
834         erase_block_wear = kzalloc(mem, GFP_KERNEL);
835         if (!erase_block_wear) {
836                 NS_ERR("Too many erase blocks for wear reporting\n");
837                 return -ENOMEM;
838         }
839         return 0;
840 }
841
842 static void update_wear(unsigned int erase_block_no)
843 {
844         unsigned long wmin = -1, wmax = 0, avg;
845         unsigned long deciles[10], decile_max[10], tot = 0;
846         unsigned int i;
847
848         if (!erase_block_wear)
849                 return;
850         total_wear += 1;
851         if (total_wear == 0)
852                 NS_ERR("Erase counter total overflow\n");
853         erase_block_wear[erase_block_no] += 1;
854         if (erase_block_wear[erase_block_no] == 0)
855                 NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
856         rptwear_cnt += 1;
857         if (rptwear_cnt < rptwear)
858                 return;
859         rptwear_cnt = 0;
860         /* Calc wear stats */
861         for (i = 0; i < wear_eb_count; ++i) {
862                 unsigned long wear = erase_block_wear[i];
863                 if (wear < wmin)
864                         wmin = wear;
865                 if (wear > wmax)
866                         wmax = wear;
867                 tot += wear;
868         }
869         for (i = 0; i < 9; ++i) {
870                 deciles[i] = 0;
871                 decile_max[i] = (wmax * (i + 1) + 5) / 10;
872         }
873         deciles[9] = 0;
874         decile_max[9] = wmax;
875         for (i = 0; i < wear_eb_count; ++i) {
876                 int d;
877                 unsigned long wear = erase_block_wear[i];
878                 for (d = 0; d < 10; ++d)
879                         if (wear <= decile_max[d]) {
880                                 deciles[d] += 1;
881                                 break;
882                         }
883         }
884         avg = tot / wear_eb_count;
885         /* Output wear report */
886         NS_INFO("*** Wear Report ***\n");
887         NS_INFO("Total numbers of erases:  %lu\n", tot);
888         NS_INFO("Number of erase blocks:   %u\n", wear_eb_count);
889         NS_INFO("Average number of erases: %lu\n", avg);
890         NS_INFO("Maximum number of erases: %lu\n", wmax);
891         NS_INFO("Minimum number of erases: %lu\n", wmin);
892         for (i = 0; i < 10; ++i) {
893                 unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
894                 if (from > decile_max[i])
895                         continue;
896                 NS_INFO("Number of ebs with erase counts from %lu to %lu : %lu\n",
897                         from,
898                         decile_max[i],
899                         deciles[i]);
900         }
901         NS_INFO("*** End of Wear Report ***\n");
902 }
903
904 /*
905  * Returns the string representation of 'state' state.
906  */
907 static char *get_state_name(uint32_t state)
908 {
909         switch (NS_STATE(state)) {
910                 case STATE_CMD_READ0:
911                         return "STATE_CMD_READ0";
912                 case STATE_CMD_READ1:
913                         return "STATE_CMD_READ1";
914                 case STATE_CMD_PAGEPROG:
915                         return "STATE_CMD_PAGEPROG";
916                 case STATE_CMD_READOOB:
917                         return "STATE_CMD_READOOB";
918                 case STATE_CMD_READSTART:
919                         return "STATE_CMD_READSTART";
920                 case STATE_CMD_ERASE1:
921                         return "STATE_CMD_ERASE1";
922                 case STATE_CMD_STATUS:
923                         return "STATE_CMD_STATUS";
924                 case STATE_CMD_STATUS_M:
925                         return "STATE_CMD_STATUS_M";
926                 case STATE_CMD_SEQIN:
927                         return "STATE_CMD_SEQIN";
928                 case STATE_CMD_READID:
929                         return "STATE_CMD_READID";
930                 case STATE_CMD_ERASE2:
931                         return "STATE_CMD_ERASE2";
932                 case STATE_CMD_RESET:
933                         return "STATE_CMD_RESET";
934                 case STATE_ADDR_PAGE:
935                         return "STATE_ADDR_PAGE";
936                 case STATE_ADDR_SEC:
937                         return "STATE_ADDR_SEC";
938                 case STATE_ADDR_ZERO:
939                         return "STATE_ADDR_ZERO";
940                 case STATE_DATAIN:
941                         return "STATE_DATAIN";
942                 case STATE_DATAOUT:
943                         return "STATE_DATAOUT";
944                 case STATE_DATAOUT_ID:
945                         return "STATE_DATAOUT_ID";
946                 case STATE_DATAOUT_STATUS:
947                         return "STATE_DATAOUT_STATUS";
948                 case STATE_DATAOUT_STATUS_M:
949                         return "STATE_DATAOUT_STATUS_M";
950                 case STATE_READY:
951                         return "STATE_READY";
952                 case STATE_UNKNOWN:
953                         return "STATE_UNKNOWN";
954         }
955
956         NS_ERR("get_state_name: unknown state, BUG\n");
957         return NULL;
958 }
959
960 /*
961  * Check if command is valid.
962  *
963  * RETURNS: 1 if wrong command, 0 if right.
964  */
965 static int check_command(int cmd)
966 {
967         switch (cmd) {
968
969         case NAND_CMD_READ0:
970         case NAND_CMD_READSTART:
971         case NAND_CMD_PAGEPROG:
972         case NAND_CMD_READOOB:
973         case NAND_CMD_ERASE1:
974         case NAND_CMD_STATUS:
975         case NAND_CMD_SEQIN:
976         case NAND_CMD_READID:
977         case NAND_CMD_ERASE2:
978         case NAND_CMD_RESET:
979         case NAND_CMD_READ1:
980                 return 0;
981
982         case NAND_CMD_STATUS_MULTI:
983         default:
984                 return 1;
985         }
986 }
987
988 /*
989  * Returns state after command is accepted by command number.
990  */
991 static uint32_t get_state_by_command(unsigned command)
992 {
993         switch (command) {
994                 case NAND_CMD_READ0:
995                         return STATE_CMD_READ0;
996                 case NAND_CMD_READ1:
997                         return STATE_CMD_READ1;
998                 case NAND_CMD_PAGEPROG:
999                         return STATE_CMD_PAGEPROG;
1000                 case NAND_CMD_READSTART:
1001                         return STATE_CMD_READSTART;
1002                 case NAND_CMD_READOOB:
1003                         return STATE_CMD_READOOB;
1004                 case NAND_CMD_ERASE1:
1005                         return STATE_CMD_ERASE1;
1006                 case NAND_CMD_STATUS:
1007                         return STATE_CMD_STATUS;
1008                 case NAND_CMD_STATUS_MULTI:
1009                         return STATE_CMD_STATUS_M;
1010                 case NAND_CMD_SEQIN:
1011                         return STATE_CMD_SEQIN;
1012                 case NAND_CMD_READID:
1013                         return STATE_CMD_READID;
1014                 case NAND_CMD_ERASE2:
1015                         return STATE_CMD_ERASE2;
1016                 case NAND_CMD_RESET:
1017                         return STATE_CMD_RESET;
1018         }
1019
1020         NS_ERR("get_state_by_command: unknown command, BUG\n");
1021         return 0;
1022 }
1023
1024 /*
1025  * Move an address byte to the correspondent internal register.
1026  */
1027 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1028 {
1029         uint byte = (uint)bt;
1030
1031         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1032                 ns->regs.column |= (byte << 8 * ns->regs.count);
1033         else {
1034                 ns->regs.row |= (byte << 8 * (ns->regs.count -
1035                                                 ns->geom.pgaddrbytes +
1036                                                 ns->geom.secaddrbytes));
1037         }
1038
1039         return;
1040 }
1041
1042 /*
1043  * Switch to STATE_READY state.
1044  */
1045 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1046 {
1047         NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1048
1049         ns->state       = STATE_READY;
1050         ns->nxstate     = STATE_UNKNOWN;
1051         ns->op          = NULL;
1052         ns->npstates    = 0;
1053         ns->stateidx    = 0;
1054         ns->regs.num    = 0;
1055         ns->regs.count  = 0;
1056         ns->regs.off    = 0;
1057         ns->regs.row    = 0;
1058         ns->regs.column = 0;
1059         ns->regs.status = status;
1060 }
1061
1062 /*
1063  * If the operation isn't known yet, try to find it in the global array
1064  * of supported operations.
1065  *
1066  * Operation can be unknown because of the following.
1067  *   1. New command was accepted and this is the firs call to find the
1068  *      correspondent states chain. In this case ns->npstates = 0;
1069  *   2. There is several operations which begin with the same command(s)
1070  *      (for example program from the second half and read from the
1071  *      second half operations both begin with the READ1 command). In this
1072  *      case the ns->pstates[] array contains previous states.
1073  *
1074  * Thus, the function tries to find operation containing the following
1075  * states (if the 'flag' parameter is 0):
1076  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1077  *
1078  * If (one and only one) matching operation is found, it is accepted (
1079  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1080  * zeroed).
1081  *
1082  * If there are several maches, the current state is pushed to the
1083  * ns->pstates.
1084  *
1085  * The operation can be unknown only while commands are input to the chip.
1086  * As soon as address command is accepted, the operation must be known.
1087  * In such situation the function is called with 'flag' != 0, and the
1088  * operation is searched using the following pattern:
1089  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1090  *
1091  * It is supposed that this pattern must either match one operation on
1092  * none. There can't be ambiguity in that case.
1093  *
1094  * If no matches found, the functions does the following:
1095  *   1. if there are saved states present, try to ignore them and search
1096  *      again only using the last command. If nothing was found, switch
1097  *      to the STATE_READY state.
1098  *   2. if there are no saved states, switch to the STATE_READY state.
1099  *
1100  * RETURNS: -2 - no matched operations found.
1101  *          -1 - several matches.
1102  *           0 - operation is found.
1103  */
1104 static int find_operation(struct nandsim *ns, uint32_t flag)
1105 {
1106         int opsfound = 0;
1107         int i, j, idx = 0;
1108
1109         for (i = 0; i < NS_OPER_NUM; i++) {
1110
1111                 int found = 1;
1112
1113                 if (!(ns->options & ops[i].reqopts))
1114                         /* Ignore operations we can't perform */
1115                         continue;
1116
1117                 if (flag) {
1118                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1119                                 continue;
1120                 } else {
1121                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1122                                 continue;
1123                 }
1124
1125                 for (j = 0; j < ns->npstates; j++)
1126                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1127                                 && (ns->options & ops[idx].reqopts)) {
1128                                 found = 0;
1129                                 break;
1130                         }
1131
1132                 if (found) {
1133                         idx = i;
1134                         opsfound += 1;
1135                 }
1136         }
1137
1138         if (opsfound == 1) {
1139                 /* Exact match */
1140                 ns->op = &ops[idx].states[0];
1141                 if (flag) {
1142                         /*
1143                          * In this case the find_operation function was
1144                          * called when address has just began input. But it isn't
1145                          * yet fully input and the current state must
1146                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1147                          * state must be the next state (ns->nxstate).
1148                          */
1149                         ns->stateidx = ns->npstates - 1;
1150                 } else {
1151                         ns->stateidx = ns->npstates;
1152                 }
1153                 ns->npstates = 0;
1154                 ns->state = ns->op[ns->stateidx];
1155                 ns->nxstate = ns->op[ns->stateidx + 1];
1156                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1157                                 idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1158                 return 0;
1159         }
1160
1161         if (opsfound == 0) {
1162                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
1163                 if (ns->npstates != 0) {
1164                         NS_DBG("find_operation: no operation found, try again with state %s\n",
1165                                         get_state_name(ns->state));
1166                         ns->npstates = 0;
1167                         return find_operation(ns, 0);
1168
1169                 }
1170                 NS_DBG("find_operation: no operations found\n");
1171                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1172                 return -2;
1173         }
1174
1175         if (flag) {
1176                 /* This shouldn't happen */
1177                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1178                 return -2;
1179         }
1180
1181         NS_DBG("find_operation: there is still ambiguity\n");
1182
1183         ns->pstates[ns->npstates++] = ns->state;
1184
1185         return -1;
1186 }
1187
1188 /*
1189  * Returns a pointer to the current page.
1190  */
1191 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1192 {
1193         return &(ns->pages[ns->regs.row]);
1194 }
1195
1196 /*
1197  * Retuns a pointer to the current byte, within the current page.
1198  */
1199 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1200 {
1201         return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1202 }
1203
1204 /*
1205  * Fill the NAND buffer with data read from the specified page.
1206  */
1207 static void read_page(struct nandsim *ns, int num)
1208 {
1209         union ns_mem *mypage;
1210
1211         mypage = NS_GET_PAGE(ns);
1212         if (mypage->byte == NULL) {
1213                 NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1214                 memset(ns->buf.byte, 0xFF, num);
1215         } else {
1216                 unsigned int page_no = ns->regs.row;
1217                 NS_DBG("read_page: page %d allocated, reading from %d\n",
1218                         ns->regs.row, ns->regs.column + ns->regs.off);
1219                 if (read_error(page_no)) {
1220                         int i;
1221                         memset(ns->buf.byte, 0xFF, num);
1222                         for (i = 0; i < num; ++i)
1223                                 ns->buf.byte[i] = random32();
1224                         NS_WARN("simulating read error in page %u\n", page_no);
1225                         return;
1226                 }
1227                 memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1228                 if (bitflips && random32() < (1 << 22)) {
1229                         int flips = 1;
1230                         if (bitflips > 1)
1231                                 flips = (random32() % (int) bitflips) + 1;
1232                         while (flips--) {
1233                                 int pos = random32() % (num * 8);
1234                                 ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1235                                 NS_WARN("read_page: flipping bit %d in page %d "
1236                                         "reading from %d ecc: corrected=%u failed=%u\n",
1237                                         pos, ns->regs.row, ns->regs.column + ns->regs.off,
1238                                         nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1239                         }
1240                 }
1241         }
1242 }
1243
1244 /*
1245  * Erase all pages in the specified sector.
1246  */
1247 static void erase_sector(struct nandsim *ns)
1248 {
1249         union ns_mem *mypage;
1250         int i;
1251
1252         mypage = NS_GET_PAGE(ns);
1253         for (i = 0; i < ns->geom.pgsec; i++) {
1254                 if (mypage->byte != NULL) {
1255                         NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1256                         kfree(mypage->byte);
1257                         mypage->byte = NULL;
1258                 }
1259                 mypage++;
1260         }
1261 }
1262
1263 /*
1264  * Program the specified page with the contents from the NAND buffer.
1265  */
1266 static int prog_page(struct nandsim *ns, int num)
1267 {
1268         int i;
1269         union ns_mem *mypage;
1270         u_char *pg_off;
1271
1272         mypage = NS_GET_PAGE(ns);
1273         if (mypage->byte == NULL) {
1274                 NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1275                 mypage->byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
1276                 if (mypage->byte == NULL) {
1277                         NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1278                         return -1;
1279                 }
1280                 memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1281         }
1282
1283         pg_off = NS_PAGE_BYTE_OFF(ns);
1284         for (i = 0; i < num; i++)
1285                 pg_off[i] &= ns->buf.byte[i];
1286
1287         return 0;
1288 }
1289
1290 /*
1291  * If state has any action bit, perform this action.
1292  *
1293  * RETURNS: 0 if success, -1 if error.
1294  */
1295 static int do_state_action(struct nandsim *ns, uint32_t action)
1296 {
1297         int num;
1298         int busdiv = ns->busw == 8 ? 1 : 2;
1299         unsigned int erase_block_no, page_no;
1300
1301         action &= ACTION_MASK;
1302
1303         /* Check that page address input is correct */
1304         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1305                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1306                 return -1;
1307         }
1308
1309         switch (action) {
1310
1311         case ACTION_CPY:
1312                 /*
1313                  * Copy page data to the internal buffer.
1314                  */
1315
1316                 /* Column shouldn't be very large */
1317                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1318                         NS_ERR("do_state_action: column number is too large\n");
1319                         break;
1320                 }
1321                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1322                 read_page(ns, num);
1323
1324                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1325                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
1326
1327                 if (ns->regs.off == 0)
1328                         NS_LOG("read page %d\n", ns->regs.row);
1329                 else if (ns->regs.off < ns->geom.pgsz)
1330                         NS_LOG("read page %d (second half)\n", ns->regs.row);
1331                 else
1332                         NS_LOG("read OOB of page %d\n", ns->regs.row);
1333
1334                 NS_UDELAY(access_delay);
1335                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1336
1337                 break;
1338
1339         case ACTION_SECERASE:
1340                 /*
1341                  * Erase sector.
1342                  */
1343
1344                 if (ns->lines.wp) {
1345                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1346                         return -1;
1347                 }
1348
1349                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1350                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
1351                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1352                         return -1;
1353                 }
1354
1355                 ns->regs.row = (ns->regs.row <<
1356                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1357                 ns->regs.column = 0;
1358
1359                 erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1360
1361                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1362                                 ns->regs.row, NS_RAW_OFFSET(ns));
1363                 NS_LOG("erase sector %u\n", erase_block_no);
1364
1365                 erase_sector(ns);
1366
1367                 NS_MDELAY(erase_delay);
1368
1369                 if (erase_block_wear)
1370                         update_wear(erase_block_no);
1371
1372                 if (erase_error(erase_block_no)) {
1373                         NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1374                         return -1;
1375                 }
1376
1377                 break;
1378
1379         case ACTION_PRGPAGE:
1380                 /*
1381                  * Programm page - move internal buffer data to the page.
1382                  */
1383
1384                 if (ns->lines.wp) {
1385                         NS_WARN("do_state_action: device is write-protected, programm\n");
1386                         return -1;
1387                 }
1388
1389                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1390                 if (num != ns->regs.count) {
1391                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1392                                         ns->regs.count, num);
1393                         return -1;
1394                 }
1395
1396                 if (prog_page(ns, num) == -1)
1397                         return -1;
1398
1399                 page_no = ns->regs.row;
1400
1401                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1402                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1403                 NS_LOG("programm page %d\n", ns->regs.row);
1404
1405                 NS_UDELAY(programm_delay);
1406                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1407
1408                 if (write_error(page_no)) {
1409                         NS_WARN("simulating write failure in page %u\n", page_no);
1410                         return -1;
1411                 }
1412
1413                 break;
1414
1415         case ACTION_ZEROOFF:
1416                 NS_DBG("do_state_action: set internal offset to 0\n");
1417                 ns->regs.off = 0;
1418                 break;
1419
1420         case ACTION_HALFOFF:
1421                 if (!(ns->options & OPT_PAGE512_8BIT)) {
1422                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1423                                 "byte page size 8x chips\n");
1424                         return -1;
1425                 }
1426                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1427                 ns->regs.off = ns->geom.pgsz/2;
1428                 break;
1429
1430         case ACTION_OOBOFF:
1431                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1432                 ns->regs.off = ns->geom.pgsz;
1433                 break;
1434
1435         default:
1436                 NS_DBG("do_state_action: BUG! unknown action\n");
1437         }
1438
1439         return 0;
1440 }
1441
1442 /*
1443  * Switch simulator's state.
1444  */
1445 static void switch_state(struct nandsim *ns)
1446 {
1447         if (ns->op) {
1448                 /*
1449                  * The current operation have already been identified.
1450                  * Just follow the states chain.
1451                  */
1452
1453                 ns->stateidx += 1;
1454                 ns->state = ns->nxstate;
1455                 ns->nxstate = ns->op[ns->stateidx + 1];
1456
1457                 NS_DBG("switch_state: operation is known, switch to the next state, "
1458                         "state: %s, nxstate: %s\n",
1459                         get_state_name(ns->state), get_state_name(ns->nxstate));
1460
1461                 /* See, whether we need to do some action */
1462                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1463                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1464                         return;
1465                 }
1466
1467         } else {
1468                 /*
1469                  * We don't yet know which operation we perform.
1470                  * Try to identify it.
1471                  */
1472
1473                 /*
1474                  *  The only event causing the switch_state function to
1475                  *  be called with yet unknown operation is new command.
1476                  */
1477                 ns->state = get_state_by_command(ns->regs.command);
1478
1479                 NS_DBG("switch_state: operation is unknown, try to find it\n");
1480
1481                 if (find_operation(ns, 0) != 0)
1482                         return;
1483
1484                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1485                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1486                         return;
1487                 }
1488         }
1489
1490         /* For 16x devices column means the page offset in words */
1491         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1492                 NS_DBG("switch_state: double the column number for 16x device\n");
1493                 ns->regs.column <<= 1;
1494         }
1495
1496         if (NS_STATE(ns->nxstate) == STATE_READY) {
1497                 /*
1498                  * The current state is the last. Return to STATE_READY
1499                  */
1500
1501                 u_char status = NS_STATUS_OK(ns);
1502
1503                 /* In case of data states, see if all bytes were input/output */
1504                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1505                         && ns->regs.count != ns->regs.num) {
1506                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
1507                                         ns->regs.num - ns->regs.count);
1508                         status = NS_STATUS_FAILED(ns);
1509                 }
1510
1511                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1512
1513                 switch_to_ready_state(ns, status);
1514
1515                 return;
1516         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1517                 /*
1518                  * If the next state is data input/output, switch to it now
1519                  */
1520
1521                 ns->state      = ns->nxstate;
1522                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1523                 ns->regs.num   = ns->regs.count = 0;
1524
1525                 NS_DBG("switch_state: the next state is data I/O, switch, "
1526                         "state: %s, nxstate: %s\n",
1527                         get_state_name(ns->state), get_state_name(ns->nxstate));
1528
1529                 /*
1530                  * Set the internal register to the count of bytes which
1531                  * are expected to be input or output
1532                  */
1533                 switch (NS_STATE(ns->state)) {
1534                         case STATE_DATAIN:
1535                         case STATE_DATAOUT:
1536                                 ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1537                                 break;
1538
1539                         case STATE_DATAOUT_ID:
1540                                 ns->regs.num = ns->geom.idbytes;
1541                                 break;
1542
1543                         case STATE_DATAOUT_STATUS:
1544                         case STATE_DATAOUT_STATUS_M:
1545                                 ns->regs.count = ns->regs.num = 0;
1546                                 break;
1547
1548                         default:
1549                                 NS_ERR("switch_state: BUG! unknown data state\n");
1550                 }
1551
1552         } else if (ns->nxstate & STATE_ADDR_MASK) {
1553                 /*
1554                  * If the next state is address input, set the internal
1555                  * register to the number of expected address bytes
1556                  */
1557
1558                 ns->regs.count = 0;
1559
1560                 switch (NS_STATE(ns->nxstate)) {
1561                         case STATE_ADDR_PAGE:
1562                                 ns->regs.num = ns->geom.pgaddrbytes;
1563
1564                                 break;
1565                         case STATE_ADDR_SEC:
1566                                 ns->regs.num = ns->geom.secaddrbytes;
1567                                 break;
1568
1569                         case STATE_ADDR_ZERO:
1570                                 ns->regs.num = 1;
1571                                 break;
1572
1573                         default:
1574                                 NS_ERR("switch_state: BUG! unknown address state\n");
1575                 }
1576         } else {
1577                 /*
1578                  * Just reset internal counters.
1579                  */
1580
1581                 ns->regs.num = 0;
1582                 ns->regs.count = 0;
1583         }
1584 }
1585
1586 static u_char ns_nand_read_byte(struct mtd_info *mtd)
1587 {
1588         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1589         u_char outb = 0x00;
1590
1591         /* Sanity and correctness checks */
1592         if (!ns->lines.ce) {
1593                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1594                 return outb;
1595         }
1596         if (ns->lines.ale || ns->lines.cle) {
1597                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1598                 return outb;
1599         }
1600         if (!(ns->state & STATE_DATAOUT_MASK)) {
1601                 NS_WARN("read_byte: unexpected data output cycle, state is %s "
1602                         "return %#x\n", get_state_name(ns->state), (uint)outb);
1603                 return outb;
1604         }
1605
1606         /* Status register may be read as many times as it is wanted */
1607         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1608                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1609                 return ns->regs.status;
1610         }
1611
1612         /* Check if there is any data in the internal buffer which may be read */
1613         if (ns->regs.count == ns->regs.num) {
1614                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1615                 return outb;
1616         }
1617
1618         switch (NS_STATE(ns->state)) {
1619                 case STATE_DATAOUT:
1620                         if (ns->busw == 8) {
1621                                 outb = ns->buf.byte[ns->regs.count];
1622                                 ns->regs.count += 1;
1623                         } else {
1624                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1625                                 ns->regs.count += 2;
1626                         }
1627                         break;
1628                 case STATE_DATAOUT_ID:
1629                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1630                         outb = ns->ids[ns->regs.count];
1631                         ns->regs.count += 1;
1632                         break;
1633                 default:
1634                         BUG();
1635         }
1636
1637         if (ns->regs.count == ns->regs.num) {
1638                 NS_DBG("read_byte: all bytes were read\n");
1639
1640                 /*
1641                  * The OPT_AUTOINCR allows to read next conseqitive pages without
1642                  * new read operation cycle.
1643                  */
1644                 if ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT) {
1645                         ns->regs.count = 0;
1646                         if (ns->regs.row + 1 < ns->geom.pgnum)
1647                                 ns->regs.row += 1;
1648                         NS_DBG("read_byte: switch to the next page (%#x)\n", ns->regs.row);
1649                         do_state_action(ns, ACTION_CPY);
1650                 }
1651                 else if (NS_STATE(ns->nxstate) == STATE_READY)
1652                         switch_state(ns);
1653
1654         }
1655
1656         return outb;
1657 }
1658
1659 static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
1660 {
1661         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1662
1663         /* Sanity and correctness checks */
1664         if (!ns->lines.ce) {
1665                 NS_ERR("write_byte: chip is disabled, ignore write\n");
1666                 return;
1667         }
1668         if (ns->lines.ale && ns->lines.cle) {
1669                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1670                 return;
1671         }
1672
1673         if (ns->lines.cle == 1) {
1674                 /*
1675                  * The byte written is a command.
1676                  */
1677
1678                 if (byte == NAND_CMD_RESET) {
1679                         NS_LOG("reset chip\n");
1680                         switch_to_ready_state(ns, NS_STATUS_OK(ns));
1681                         return;
1682                 }
1683
1684                 /*
1685                  * Chip might still be in STATE_DATAOUT
1686                  * (if OPT_AUTOINCR feature is supported), STATE_DATAOUT_STATUS or
1687                  * STATE_DATAOUT_STATUS_M state. If so, switch state.
1688                  */
1689                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1690                         || NS_STATE(ns->state) == STATE_DATAOUT_STATUS_M
1691                         || ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT))
1692                         switch_state(ns);
1693
1694                 /* Check if chip is expecting command */
1695                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
1696                         /*
1697                          * We are in situation when something else (not command)
1698                          * was expected but command was input. In this case ignore
1699                          * previous command(s)/state(s) and accept the last one.
1700                          */
1701                         NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
1702                                 "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
1703                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1704                 }
1705
1706                 /* Check that the command byte is correct */
1707                 if (check_command(byte)) {
1708                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1709                         return;
1710                 }
1711
1712                 NS_DBG("command byte corresponding to %s state accepted\n",
1713                         get_state_name(get_state_by_command(byte)));
1714                 ns->regs.command = byte;
1715                 switch_state(ns);
1716
1717         } else if (ns->lines.ale == 1) {
1718                 /*
1719                  * The byte written is an address.
1720                  */
1721
1722                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
1723
1724                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
1725
1726                         if (find_operation(ns, 1) < 0)
1727                                 return;
1728
1729                         if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1730                                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1731                                 return;
1732                         }
1733
1734                         ns->regs.count = 0;
1735                         switch (NS_STATE(ns->nxstate)) {
1736                                 case STATE_ADDR_PAGE:
1737                                         ns->regs.num = ns->geom.pgaddrbytes;
1738                                         break;
1739                                 case STATE_ADDR_SEC:
1740                                         ns->regs.num = ns->geom.secaddrbytes;
1741                                         break;
1742                                 case STATE_ADDR_ZERO:
1743                                         ns->regs.num = 1;
1744                                         break;
1745                                 default:
1746                                         BUG();
1747                         }
1748                 }
1749
1750                 /* Check that chip is expecting address */
1751                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
1752                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
1753                                 "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
1754                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1755                         return;
1756                 }
1757
1758                 /* Check if this is expected byte */
1759                 if (ns->regs.count == ns->regs.num) {
1760                         NS_ERR("write_byte: no more address bytes expected\n");
1761                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1762                         return;
1763                 }
1764
1765                 accept_addr_byte(ns, byte);
1766
1767                 ns->regs.count += 1;
1768
1769                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
1770                                 (uint)byte, ns->regs.count, ns->regs.num);
1771
1772                 if (ns->regs.count == ns->regs.num) {
1773                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
1774                         switch_state(ns);
1775                 }
1776
1777         } else {
1778                 /*
1779                  * The byte written is an input data.
1780                  */
1781
1782                 /* Check that chip is expecting data input */
1783                 if (!(ns->state & STATE_DATAIN_MASK)) {
1784                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
1785                                 "switch to %s\n", (uint)byte,
1786                                 get_state_name(ns->state), get_state_name(STATE_READY));
1787                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1788                         return;
1789                 }
1790
1791                 /* Check if this is expected byte */
1792                 if (ns->regs.count == ns->regs.num) {
1793                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
1794                                         ns->regs.num);
1795                         return;
1796                 }
1797
1798                 if (ns->busw == 8) {
1799                         ns->buf.byte[ns->regs.count] = byte;
1800                         ns->regs.count += 1;
1801                 } else {
1802                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
1803                         ns->regs.count += 2;
1804                 }
1805         }
1806
1807         return;
1808 }
1809
1810 static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask)
1811 {
1812         struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1813
1814         ns->lines.cle = bitmask & NAND_CLE ? 1 : 0;
1815         ns->lines.ale = bitmask & NAND_ALE ? 1 : 0;
1816         ns->lines.ce = bitmask & NAND_NCE ? 1 : 0;
1817
1818         if (cmd != NAND_CMD_NONE)
1819                 ns_nand_write_byte(mtd, cmd);
1820 }
1821
1822 static int ns_device_ready(struct mtd_info *mtd)
1823 {
1824         NS_DBG("device_ready\n");
1825         return 1;
1826 }
1827
1828 static uint16_t ns_nand_read_word(struct mtd_info *mtd)
1829 {
1830         struct nand_chip *chip = (struct nand_chip *)mtd->priv;
1831
1832         NS_DBG("read_word\n");
1833
1834         return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
1835 }
1836
1837 static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
1838 {
1839         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1840
1841         /* Check that chip is expecting data input */
1842         if (!(ns->state & STATE_DATAIN_MASK)) {
1843                 NS_ERR("write_buf: data input isn't expected, state is %s, "
1844                         "switch to STATE_READY\n", get_state_name(ns->state));
1845                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1846                 return;
1847         }
1848
1849         /* Check if these are expected bytes */
1850         if (ns->regs.count + len > ns->regs.num) {
1851                 NS_ERR("write_buf: too many input bytes\n");
1852                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1853                 return;
1854         }
1855
1856         memcpy(ns->buf.byte + ns->regs.count, buf, len);
1857         ns->regs.count += len;
1858
1859         if (ns->regs.count == ns->regs.num) {
1860                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
1861         }
1862 }
1863
1864 static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
1865 {
1866         struct nandsim *ns = (struct nandsim *)((struct nand_chip *)mtd->priv)->priv;
1867
1868         /* Sanity and correctness checks */
1869         if (!ns->lines.ce) {
1870                 NS_ERR("read_buf: chip is disabled\n");
1871                 return;
1872         }
1873         if (ns->lines.ale || ns->lines.cle) {
1874                 NS_ERR("read_buf: ALE or CLE pin is high\n");
1875                 return;
1876         }
1877         if (!(ns->state & STATE_DATAOUT_MASK)) {
1878                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
1879                         get_state_name(ns->state));
1880                 return;
1881         }
1882
1883         if (NS_STATE(ns->state) != STATE_DATAOUT) {
1884                 int i;
1885
1886                 for (i = 0; i < len; i++)
1887                         buf[i] = ((struct nand_chip *)mtd->priv)->read_byte(mtd);
1888
1889                 return;
1890         }
1891
1892         /* Check if these are expected bytes */
1893         if (ns->regs.count + len > ns->regs.num) {
1894                 NS_ERR("read_buf: too many bytes to read\n");
1895                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1896                 return;
1897         }
1898
1899         memcpy(buf, ns->buf.byte + ns->regs.count, len);
1900         ns->regs.count += len;
1901
1902         if (ns->regs.count == ns->regs.num) {
1903                 if ((ns->options & OPT_AUTOINCR) && NS_STATE(ns->state) == STATE_DATAOUT) {
1904                         ns->regs.count = 0;
1905                         if (ns->regs.row + 1 < ns->geom.pgnum)
1906                                 ns->regs.row += 1;
1907                         NS_DBG("read_buf: switch to the next page (%#x)\n", ns->regs.row);
1908                         do_state_action(ns, ACTION_CPY);
1909                 }
1910                 else if (NS_STATE(ns->nxstate) == STATE_READY)
1911                         switch_state(ns);
1912         }
1913
1914         return;
1915 }
1916
1917 static int ns_nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
1918 {
1919         ns_nand_read_buf(mtd, (u_char *)&ns_verify_buf[0], len);
1920
1921         if (!memcmp(buf, &ns_verify_buf[0], len)) {
1922                 NS_DBG("verify_buf: the buffer is OK\n");
1923                 return 0;
1924         } else {
1925                 NS_DBG("verify_buf: the buffer is wrong\n");
1926                 return -EFAULT;
1927         }
1928 }
1929
1930 /*
1931  * Module initialization function
1932  */
1933 static int __init ns_init_module(void)
1934 {
1935         struct nand_chip *chip;
1936         struct nandsim *nand;
1937         int retval = -ENOMEM, i;
1938
1939         if (bus_width != 8 && bus_width != 16) {
1940                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
1941                 return -EINVAL;
1942         }
1943
1944         /* Allocate and initialize mtd_info, nand_chip and nandsim structures */
1945         nsmtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip)
1946                                 + sizeof(struct nandsim), GFP_KERNEL);
1947         if (!nsmtd) {
1948                 NS_ERR("unable to allocate core structures.\n");
1949                 return -ENOMEM;
1950         }
1951         chip        = (struct nand_chip *)(nsmtd + 1);
1952         nsmtd->priv = (void *)chip;
1953         nand        = (struct nandsim *)(chip + 1);
1954         chip->priv  = (void *)nand;
1955
1956         /*
1957          * Register simulator's callbacks.
1958          */
1959         chip->cmd_ctrl   = ns_hwcontrol;
1960         chip->read_byte  = ns_nand_read_byte;
1961         chip->dev_ready  = ns_device_ready;
1962         chip->write_buf  = ns_nand_write_buf;
1963         chip->read_buf   = ns_nand_read_buf;
1964         chip->verify_buf = ns_nand_verify_buf;
1965         chip->read_word  = ns_nand_read_word;
1966         chip->ecc.mode   = NAND_ECC_SOFT;
1967         /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
1968         /* and 'badblocks' parameters to work */
1969         chip->options   |= NAND_SKIP_BBTSCAN;
1970
1971         /*
1972          * Perform minimum nandsim structure initialization to handle
1973          * the initial ID read command correctly
1974          */
1975         if (third_id_byte != 0xFF || fourth_id_byte != 0xFF)
1976                 nand->geom.idbytes = 4;
1977         else
1978                 nand->geom.idbytes = 2;
1979         nand->regs.status = NS_STATUS_OK(nand);
1980         nand->nxstate = STATE_UNKNOWN;
1981         nand->options |= OPT_PAGE256; /* temporary value */
1982         nand->ids[0] = first_id_byte;
1983         nand->ids[1] = second_id_byte;
1984         nand->ids[2] = third_id_byte;
1985         nand->ids[3] = fourth_id_byte;
1986         if (bus_width == 16) {
1987                 nand->busw = 16;
1988                 chip->options |= NAND_BUSWIDTH_16;
1989         }
1990
1991         nsmtd->owner = THIS_MODULE;
1992
1993         if ((retval = parse_weakblocks()) != 0)
1994                 goto error;
1995
1996         if ((retval = parse_weakpages()) != 0)
1997                 goto error;
1998
1999         if ((retval = parse_gravepages()) != 0)
2000                 goto error;
2001
2002         if ((retval = nand_scan(nsmtd, 1)) != 0) {
2003                 NS_ERR("can't register NAND Simulator\n");
2004                 if (retval > 0)
2005                         retval = -ENXIO;
2006                 goto error;
2007         }
2008
2009         if (overridesize) {
2010                 u_int32_t new_size = nsmtd->erasesize << overridesize;
2011                 if (new_size >> overridesize != nsmtd->erasesize) {
2012                         NS_ERR("overridesize is too big\n");
2013                         goto err_exit;
2014                 }
2015                 /* N.B. This relies on nand_scan not doing anything with the size before we change it */
2016                 nsmtd->size = new_size;
2017                 chip->chipsize = new_size;
2018                 chip->chip_shift = ffs(new_size) - 1;
2019         }
2020
2021         if ((retval = setup_wear_reporting(nsmtd)) != 0)
2022                 goto err_exit;
2023
2024         if ((retval = init_nandsim(nsmtd)) != 0)
2025                 goto err_exit;
2026
2027         if ((retval = parse_badblocks(nand, nsmtd)) != 0)
2028                 goto err_exit;
2029
2030         if ((retval = nand_default_bbt(nsmtd)) != 0)
2031                 goto err_exit;
2032
2033         /* Register NAND partitions */
2034         if ((retval = add_mtd_partitions(nsmtd, &nand->partitions[0], nand->nbparts)) != 0)
2035                 goto err_exit;
2036
2037         return 0;
2038
2039 err_exit:
2040         free_nandsim(nand);
2041         nand_release(nsmtd);
2042         for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i)
2043                 kfree(nand->partitions[i].name);
2044 error:
2045         kfree(nsmtd);
2046         free_lists();
2047
2048         return retval;
2049 }
2050
2051 module_init(ns_init_module);
2052
2053 /*
2054  * Module clean-up function
2055  */
2056 static void __exit ns_cleanup_module(void)
2057 {
2058         struct nandsim *ns = (struct nandsim *)(((struct nand_chip *)nsmtd->priv)->priv);
2059         int i;
2060
2061         free_nandsim(ns);    /* Free nandsim private resources */
2062         nand_release(nsmtd); /* Unregister driver */
2063         for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2064                 kfree(ns->partitions[i].name);
2065         kfree(nsmtd);        /* Free other structures */
2066         free_lists();
2067 }
2068
2069 module_exit(ns_cleanup_module);
2070
2071 MODULE_LICENSE ("GPL");
2072 MODULE_AUTHOR ("Artem B. Bityuckiy");
2073 MODULE_DESCRIPTION ("The NAND flash simulator");