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1 /*
2  * NAND flash simulator.
3  *
4  * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org>
5  *
6  * Copyright (C) 2004 Nokia Corporation
7  *
8  * Note: NS means "NAND Simulator".
9  * Note: Input means input TO flash chip, output means output FROM chip.
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms of the GNU General Public License as published by the
13  * Free Software Foundation; either version 2, or (at your option) any later
14  * version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
19  * Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
24  */
25 
26 #include <linux/init.h>
27 #include <linux/types.h>
28 #include <linux/module.h>
29 #include <linux/moduleparam.h>
30 #include <linux/vmalloc.h>
31 #include <linux/math64.h>
32 #include <linux/slab.h>
33 #include <linux/errno.h>
34 #include <linux/string.h>
35 #include <linux/mtd/mtd.h>
36 #include <linux/mtd/nand.h>
37 #include <linux/mtd/nand_bch.h>
38 #include <linux/mtd/partitions.h>
39 #include <linux/delay.h>
40 #include <linux/list.h>
41 #include <linux/random.h>
42 #include <linux/sched.h>
43 #include <linux/fs.h>
44 #include <linux/pagemap.h>
45 #include <linux/seq_file.h>
46 #include <linux/debugfs.h>
47 
48 /* Default simulator parameters values */
49 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
50     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
51     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
52     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
53 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
54 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
55 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
56 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
57 #endif
58 
59 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
60 #define CONFIG_NANDSIM_ACCESS_DELAY 25
61 #endif
62 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
63 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
64 #endif
65 #ifndef CONFIG_NANDSIM_ERASE_DELAY
66 #define CONFIG_NANDSIM_ERASE_DELAY 2
67 #endif
68 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
69 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
70 #endif
71 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
72 #define CONFIG_NANDSIM_INPUT_CYCLE  50
73 #endif
74 #ifndef CONFIG_NANDSIM_BUS_WIDTH
75 #define CONFIG_NANDSIM_BUS_WIDTH  8
76 #endif
77 #ifndef CONFIG_NANDSIM_DO_DELAYS
78 #define CONFIG_NANDSIM_DO_DELAYS  0
79 #endif
80 #ifndef CONFIG_NANDSIM_LOG
81 #define CONFIG_NANDSIM_LOG        0
82 #endif
83 #ifndef CONFIG_NANDSIM_DBG
84 #define CONFIG_NANDSIM_DBG        0
85 #endif
86 #ifndef CONFIG_NANDSIM_MAX_PARTS
87 #define CONFIG_NANDSIM_MAX_PARTS  32
88 #endif
89 
90 static uint first_id_byte  = CONFIG_NANDSIM_FIRST_ID_BYTE;
91 static uint second_id_byte = CONFIG_NANDSIM_SECOND_ID_BYTE;
92 static uint third_id_byte  = CONFIG_NANDSIM_THIRD_ID_BYTE;
93 static uint fourth_id_byte = CONFIG_NANDSIM_FOURTH_ID_BYTE;
94 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
95 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
96 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
97 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
98 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
99 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
100 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
101 static uint log            = CONFIG_NANDSIM_LOG;
102 static uint dbg            = CONFIG_NANDSIM_DBG;
103 static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];
104 static unsigned int parts_num;
105 static char *badblocks = NULL;
106 static char *weakblocks = NULL;
107 static char *weakpages = NULL;
108 static unsigned int bitflips = 0;
109 static char *gravepages = NULL;
110 static unsigned int overridesize = 0;
111 static char *cache_file = NULL;
112 static unsigned int bbt;
113 static unsigned int bch;
114 
115 module_param(first_id_byte,  uint, 0400);
116 module_param(second_id_byte, uint, 0400);
117 module_param(third_id_byte,  uint, 0400);
118 module_param(fourth_id_byte, uint, 0400);
119 module_param(access_delay,   uint, 0400);
120 module_param(programm_delay, uint, 0400);
121 module_param(erase_delay,    uint, 0400);
122 module_param(output_cycle,   uint, 0400);
123 module_param(input_cycle,    uint, 0400);
124 module_param(bus_width,      uint, 0400);
125 module_param(do_delays,      uint, 0400);
126 module_param(log,            uint, 0400);
127 module_param(dbg,            uint, 0400);
128 module_param_array(parts, ulong, &parts_num, 0400);
129 module_param(badblocks,      charp, 0400);
130 module_param(weakblocks,     charp, 0400);
131 module_param(weakpages,      charp, 0400);
132 module_param(bitflips,       uint, 0400);
133 module_param(gravepages,     charp, 0400);
134 module_param(overridesize,   uint, 0400);
135 module_param(cache_file,     charp, 0400);
136 module_param(bbt,	     uint, 0400);
137 module_param(bch,	     uint, 0400);
138 
139 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID)");
140 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID)");
141 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command");
142 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command");
143 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");
144 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
145 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
146 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");
147 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");
148 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
149 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
150 MODULE_PARM_DESC(log,            "Perform logging if not zero");
151 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
152 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
153 /* Page and erase block positions for the following parameters are independent of any partitions */
154 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
155 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
156 				 " separated by commas e.g. 113:2 means eb 113"
157 				 " can be erased only twice before failing");
158 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
159 				 " separated by commas e.g. 1401:2 means page 1401"
160 				 " can be written only twice before failing");
161 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
162 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
163 				 " separated by commas e.g. 1401:2 means page 1401"
164 				 " can be read only twice before failing");
165 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
166 				 "The size is specified in erase blocks and as the exponent of a power of two"
167 				 " e.g. 5 means a size of 32 erase blocks");
168 MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");
169 MODULE_PARM_DESC(bbt,		 "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");
170 MODULE_PARM_DESC(bch,		 "Enable BCH ecc and set how many bits should "
171 				 "be correctable in 512-byte blocks");
172 
173 /* The largest possible page size */
174 #define NS_LARGEST_PAGE_SIZE	4096
175 
176 /* The prefix for simulator output */
177 #define NS_OUTPUT_PREFIX "[nandsim]"
178 
179 /* Simulator's output macros (logging, debugging, warning, error) */
180 #define NS_LOG(args...) \
181 	do { if (log) printk(KERN_DEBUG NS_OUTPUT_PREFIX " log: " args); } while(0)
182 #define NS_DBG(args...) \
183 	do { if (dbg) printk(KERN_DEBUG NS_OUTPUT_PREFIX " debug: " args); } while(0)
184 #define NS_WARN(args...) \
185 	do { printk(KERN_WARNING NS_OUTPUT_PREFIX " warning: " args); } while(0)
186 #define NS_ERR(args...) \
187 	do { printk(KERN_ERR NS_OUTPUT_PREFIX " error: " args); } while(0)
188 #define NS_INFO(args...) \
189 	do { printk(KERN_INFO NS_OUTPUT_PREFIX " " args); } while(0)
190 
191 /* Busy-wait delay macros (microseconds, milliseconds) */
192 #define NS_UDELAY(us) \
193         do { if (do_delays) udelay(us); } while(0)
194 #define NS_MDELAY(us) \
195         do { if (do_delays) mdelay(us); } while(0)
196 
197 /* Is the nandsim structure initialized ? */
198 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
199 
200 /* Good operation completion status */
201 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
202 
203 /* Operation failed completion status */
204 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
205 
206 /* Calculate the page offset in flash RAM image by (row, column) address */
207 #define NS_RAW_OFFSET(ns) \
208 	(((ns)->regs.row * (ns)->geom.pgszoob) + (ns)->regs.column)
209 
210 /* Calculate the OOB offset in flash RAM image by (row, column) address */
211 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
212 
213 /* After a command is input, the simulator goes to one of the following states */
214 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
215 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
216 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
217 #define STATE_CMD_PAGEPROG     0x00000004 /* start page program */
218 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
219 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
220 #define STATE_CMD_STATUS       0x00000007 /* read status */
221 #define STATE_CMD_SEQIN        0x00000009 /* sequential data input */
222 #define STATE_CMD_READID       0x0000000A /* read ID */
223 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
224 #define STATE_CMD_RESET        0x0000000C /* reset */
225 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
226 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
227 #define STATE_CMD_MASK         0x0000000F /* command states mask */
228 
229 /* After an address is input, the simulator goes to one of these states */
230 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
231 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
232 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
233 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
234 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
235 
236 /* During data input/output the simulator is in these states */
237 #define STATE_DATAIN           0x00000100 /* waiting for data input */
238 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
239 
240 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
241 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
242 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
243 #define STATE_DATAOUT_STATUS_M 0x00004000 /* waiting for multi-plane status output */
244 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
245 
246 /* Previous operation is done, ready to accept new requests */
247 #define STATE_READY            0x00000000
248 
249 /* This state is used to mark that the next state isn't known yet */
250 #define STATE_UNKNOWN          0x10000000
251 
252 /* Simulator's actions bit masks */
253 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
254 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
255 #define ACTION_SECERASE  0x00300000 /* erase sector */
256 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
257 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
258 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
259 #define ACTION_MASK      0x00700000 /* action mask */
260 
261 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
262 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
263 
264 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
265 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
266 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
267 #define OPT_SMARTMEDIA   0x00000010 /* SmartMedia technology chips */
268 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
269 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
270 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
271 #define OPT_SMALLPAGE    (OPT_PAGE512) /* 512-byte page chips */
272 
273 /* Remove action bits from state */
274 #define NS_STATE(x) ((x) & ~ACTION_MASK)
275 
276 /*
277  * Maximum previous states which need to be saved. Currently saving is
278  * only needed for page program operation with preceded read command
279  * (which is only valid for 512-byte pages).
280  */
281 #define NS_MAX_PREVSTATES 1
282 
283 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
284 #define NS_MAX_HELD_PAGES 16
285 
286 struct nandsim_debug_info {
287 	struct dentry *dfs_root;
288 	struct dentry *dfs_wear_report;
289 };
290 
291 /*
292  * A union to represent flash memory contents and flash buffer.
293  */
294 union ns_mem {
295 	u_char *byte;    /* for byte access */
296 	uint16_t *word;  /* for 16-bit word access */
297 };
298 
299 /*
300  * The structure which describes all the internal simulator data.
301  */
302 struct nandsim {
303 	struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
304 	unsigned int nbparts;
305 
306 	uint busw;              /* flash chip bus width (8 or 16) */
307 	u_char ids[4];          /* chip's ID bytes */
308 	uint32_t options;       /* chip's characteristic bits */
309 	uint32_t state;         /* current chip state */
310 	uint32_t nxstate;       /* next expected state */
311 
312 	uint32_t *op;           /* current operation, NULL operations isn't known yet  */
313 	uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
314 	uint16_t npstates;      /* number of previous states saved */
315 	uint16_t stateidx;      /* current state index */
316 
317 	/* The simulated NAND flash pages array */
318 	union ns_mem *pages;
319 
320 	/* Slab allocator for nand pages */
321 	struct kmem_cache *nand_pages_slab;
322 
323 	/* Internal buffer of page + OOB size bytes */
324 	union ns_mem buf;
325 
326 	/* NAND flash "geometry" */
327 	struct {
328 		uint64_t totsz;     /* total flash size, bytes */
329 		uint32_t secsz;     /* flash sector (erase block) size, bytes */
330 		uint pgsz;          /* NAND flash page size, bytes */
331 		uint oobsz;         /* page OOB area size, bytes */
332 		uint64_t totszoob;  /* total flash size including OOB, bytes */
333 		uint pgszoob;       /* page size including OOB , bytes*/
334 		uint secszoob;      /* sector size including OOB, bytes */
335 		uint pgnum;         /* total number of pages */
336 		uint pgsec;         /* number of pages per sector */
337 		uint secshift;      /* bits number in sector size */
338 		uint pgshift;       /* bits number in page size */
339 		uint pgaddrbytes;   /* bytes per page address */
340 		uint secaddrbytes;  /* bytes per sector address */
341 		uint idbytes;       /* the number ID bytes that this chip outputs */
342 	} geom;
343 
344 	/* NAND flash internal registers */
345 	struct {
346 		unsigned command; /* the command register */
347 		u_char   status;  /* the status register */
348 		uint     row;     /* the page number */
349 		uint     column;  /* the offset within page */
350 		uint     count;   /* internal counter */
351 		uint     num;     /* number of bytes which must be processed */
352 		uint     off;     /* fixed page offset */
353 	} regs;
354 
355 	/* NAND flash lines state */
356         struct {
357                 int ce;  /* chip Enable */
358                 int cle; /* command Latch Enable */
359                 int ale; /* address Latch Enable */
360                 int wp;  /* write Protect */
361         } lines;
362 
363 	/* Fields needed when using a cache file */
364 	struct file *cfile; /* Open file */
365 	unsigned long *pages_written; /* Which pages have been written */
366 	void *file_buf;
367 	struct page *held_pages[NS_MAX_HELD_PAGES];
368 	int held_cnt;
369 
370 	struct nandsim_debug_info dbg;
371 };
372 
373 /*
374  * Operations array. To perform any operation the simulator must pass
375  * through the correspondent states chain.
376  */
377 static struct nandsim_operations {
378 	uint32_t reqopts;  /* options which are required to perform the operation */
379 	uint32_t states[NS_OPER_STATES]; /* operation's states */
380 } ops[NS_OPER_NUM] = {
381 	/* Read page + OOB from the beginning */
382 	{OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
383 			STATE_DATAOUT, STATE_READY}},
384 	/* Read page + OOB from the second half */
385 	{OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
386 			STATE_DATAOUT, STATE_READY}},
387 	/* Read OOB */
388 	{OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
389 			STATE_DATAOUT, STATE_READY}},
390 	/* Program page starting from the beginning */
391 	{OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
392 			STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
393 	/* Program page starting from the beginning */
394 	{OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
395 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
396 	/* Program page starting from the second half */
397 	{OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
398 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
399 	/* Program OOB */
400 	{OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
401 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
402 	/* Erase sector */
403 	{OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
404 	/* Read status */
405 	{OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
406 	/* Read ID */
407 	{OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
408 	/* Large page devices read page */
409 	{OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
410 			       STATE_DATAOUT, STATE_READY}},
411 	/* Large page devices random page read */
412 	{OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
413 			       STATE_DATAOUT, STATE_READY}},
414 };
415 
416 struct weak_block {
417 	struct list_head list;
418 	unsigned int erase_block_no;
419 	unsigned int max_erases;
420 	unsigned int erases_done;
421 };
422 
423 static LIST_HEAD(weak_blocks);
424 
425 struct weak_page {
426 	struct list_head list;
427 	unsigned int page_no;
428 	unsigned int max_writes;
429 	unsigned int writes_done;
430 };
431 
432 static LIST_HEAD(weak_pages);
433 
434 struct grave_page {
435 	struct list_head list;
436 	unsigned int page_no;
437 	unsigned int max_reads;
438 	unsigned int reads_done;
439 };
440 
441 static LIST_HEAD(grave_pages);
442 
443 static unsigned long *erase_block_wear = NULL;
444 static unsigned int wear_eb_count = 0;
445 static unsigned long total_wear = 0;
446 
447 /* MTD structure for NAND controller */
448 static struct mtd_info *nsmtd;
449 
nandsim_debugfs_show(struct seq_file * m,void * private)450 static int nandsim_debugfs_show(struct seq_file *m, void *private)
451 {
452 	unsigned long wmin = -1, wmax = 0, avg;
453 	unsigned long deciles[10], decile_max[10], tot = 0;
454 	unsigned int i;
455 
456 	/* Calc wear stats */
457 	for (i = 0; i < wear_eb_count; ++i) {
458 		unsigned long wear = erase_block_wear[i];
459 		if (wear < wmin)
460 			wmin = wear;
461 		if (wear > wmax)
462 			wmax = wear;
463 		tot += wear;
464 	}
465 
466 	for (i = 0; i < 9; ++i) {
467 		deciles[i] = 0;
468 		decile_max[i] = (wmax * (i + 1) + 5) / 10;
469 	}
470 	deciles[9] = 0;
471 	decile_max[9] = wmax;
472 	for (i = 0; i < wear_eb_count; ++i) {
473 		int d;
474 		unsigned long wear = erase_block_wear[i];
475 		for (d = 0; d < 10; ++d)
476 			if (wear <= decile_max[d]) {
477 				deciles[d] += 1;
478 				break;
479 			}
480 	}
481 	avg = tot / wear_eb_count;
482 
483 	/* Output wear report */
484 	seq_printf(m, "Total numbers of erases:  %lu\n", tot);
485 	seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);
486 	seq_printf(m, "Average number of erases: %lu\n", avg);
487 	seq_printf(m, "Maximum number of erases: %lu\n", wmax);
488 	seq_printf(m, "Minimum number of erases: %lu\n", wmin);
489 	for (i = 0; i < 10; ++i) {
490 		unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
491 		if (from > decile_max[i])
492 			continue;
493 		seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
494 			from,
495 			decile_max[i],
496 			deciles[i]);
497 	}
498 
499 	return 0;
500 }
501 
nandsim_debugfs_open(struct inode * inode,struct file * file)502 static int nandsim_debugfs_open(struct inode *inode, struct file *file)
503 {
504 	return single_open(file, nandsim_debugfs_show, inode->i_private);
505 }
506 
507 static const struct file_operations dfs_fops = {
508 	.open		= nandsim_debugfs_open,
509 	.read		= seq_read,
510 	.llseek		= seq_lseek,
511 	.release	= single_release,
512 };
513 
514 /**
515  * nandsim_debugfs_create - initialize debugfs
516  * @dev: nandsim device description object
517  *
518  * This function creates all debugfs files for UBI device @ubi. Returns zero in
519  * case of success and a negative error code in case of failure.
520  */
nandsim_debugfs_create(struct nandsim * dev)521 static int nandsim_debugfs_create(struct nandsim *dev)
522 {
523 	struct nandsim_debug_info *dbg = &dev->dbg;
524 	struct dentry *dent;
525 	int err;
526 
527 	if (!IS_ENABLED(CONFIG_DEBUG_FS))
528 		return 0;
529 
530 	dent = debugfs_create_dir("nandsim", NULL);
531 	if (IS_ERR_OR_NULL(dent)) {
532 		int err = dent ? -ENODEV : PTR_ERR(dent);
533 
534 		NS_ERR("cannot create \"nandsim\" debugfs directory, err %d\n",
535 			err);
536 		return err;
537 	}
538 	dbg->dfs_root = dent;
539 
540 	dent = debugfs_create_file("wear_report", S_IRUSR,
541 				   dbg->dfs_root, dev, &dfs_fops);
542 	if (IS_ERR_OR_NULL(dent))
543 		goto out_remove;
544 	dbg->dfs_wear_report = dent;
545 
546 	return 0;
547 
548 out_remove:
549 	debugfs_remove_recursive(dbg->dfs_root);
550 	err = dent ? PTR_ERR(dent) : -ENODEV;
551 	return err;
552 }
553 
554 /**
555  * nandsim_debugfs_remove - destroy all debugfs files
556  */
nandsim_debugfs_remove(struct nandsim * ns)557 static void nandsim_debugfs_remove(struct nandsim *ns)
558 {
559 	if (IS_ENABLED(CONFIG_DEBUG_FS))
560 		debugfs_remove_recursive(ns->dbg.dfs_root);
561 }
562 
563 /*
564  * Allocate array of page pointers, create slab allocation for an array
565  * and initialize the array by NULL pointers.
566  *
567  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
568  */
alloc_device(struct nandsim * ns)569 static int alloc_device(struct nandsim *ns)
570 {
571 	struct file *cfile;
572 	int i, err;
573 
574 	if (cache_file) {
575 		cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
576 		if (IS_ERR(cfile))
577 			return PTR_ERR(cfile);
578 		if (!(cfile->f_mode & FMODE_CAN_READ)) {
579 			NS_ERR("alloc_device: cache file not readable\n");
580 			err = -EINVAL;
581 			goto err_close;
582 		}
583 		if (!(cfile->f_mode & FMODE_CAN_WRITE)) {
584 			NS_ERR("alloc_device: cache file not writeable\n");
585 			err = -EINVAL;
586 			goto err_close;
587 		}
588 		ns->pages_written = vzalloc(BITS_TO_LONGS(ns->geom.pgnum) *
589 					    sizeof(unsigned long));
590 		if (!ns->pages_written) {
591 			NS_ERR("alloc_device: unable to allocate pages written array\n");
592 			err = -ENOMEM;
593 			goto err_close;
594 		}
595 		ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
596 		if (!ns->file_buf) {
597 			NS_ERR("alloc_device: unable to allocate file buf\n");
598 			err = -ENOMEM;
599 			goto err_free;
600 		}
601 		ns->cfile = cfile;
602 		return 0;
603 	}
604 
605 	ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem));
606 	if (!ns->pages) {
607 		NS_ERR("alloc_device: unable to allocate page array\n");
608 		return -ENOMEM;
609 	}
610 	for (i = 0; i < ns->geom.pgnum; i++) {
611 		ns->pages[i].byte = NULL;
612 	}
613 	ns->nand_pages_slab = kmem_cache_create("nandsim",
614 						ns->geom.pgszoob, 0, 0, NULL);
615 	if (!ns->nand_pages_slab) {
616 		NS_ERR("cache_create: unable to create kmem_cache\n");
617 		return -ENOMEM;
618 	}
619 
620 	return 0;
621 
622 err_free:
623 	vfree(ns->pages_written);
624 err_close:
625 	filp_close(cfile, NULL);
626 	return err;
627 }
628 
629 /*
630  * Free any allocated pages, and free the array of page pointers.
631  */
free_device(struct nandsim * ns)632 static void free_device(struct nandsim *ns)
633 {
634 	int i;
635 
636 	if (ns->cfile) {
637 		kfree(ns->file_buf);
638 		vfree(ns->pages_written);
639 		filp_close(ns->cfile, NULL);
640 		return;
641 	}
642 
643 	if (ns->pages) {
644 		for (i = 0; i < ns->geom.pgnum; i++) {
645 			if (ns->pages[i].byte)
646 				kmem_cache_free(ns->nand_pages_slab,
647 						ns->pages[i].byte);
648 		}
649 		kmem_cache_destroy(ns->nand_pages_slab);
650 		vfree(ns->pages);
651 	}
652 }
653 
get_partition_name(int i)654 static char *get_partition_name(int i)
655 {
656 	return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i);
657 }
658 
659 /*
660  * Initialize the nandsim structure.
661  *
662  * RETURNS: 0 if success, -ERRNO if failure.
663  */
init_nandsim(struct mtd_info * mtd)664 static int init_nandsim(struct mtd_info *mtd)
665 {
666 	struct nand_chip *chip = mtd->priv;
667 	struct nandsim   *ns   = chip->priv;
668 	int i, ret = 0;
669 	uint64_t remains;
670 	uint64_t next_offset;
671 
672 	if (NS_IS_INITIALIZED(ns)) {
673 		NS_ERR("init_nandsim: nandsim is already initialized\n");
674 		return -EIO;
675 	}
676 
677 	/* Force mtd to not do delays */
678 	chip->chip_delay = 0;
679 
680 	/* Initialize the NAND flash parameters */
681 	ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
682 	ns->geom.totsz    = mtd->size;
683 	ns->geom.pgsz     = mtd->writesize;
684 	ns->geom.oobsz    = mtd->oobsize;
685 	ns->geom.secsz    = mtd->erasesize;
686 	ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
687 	ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
688 	ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
689 	ns->geom.secshift = ffs(ns->geom.secsz) - 1;
690 	ns->geom.pgshift  = chip->page_shift;
691 	ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
692 	ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
693 	ns->options = 0;
694 
695 	if (ns->geom.pgsz == 512) {
696 		ns->options |= OPT_PAGE512;
697 		if (ns->busw == 8)
698 			ns->options |= OPT_PAGE512_8BIT;
699 	} else if (ns->geom.pgsz == 2048) {
700 		ns->options |= OPT_PAGE2048;
701 	} else if (ns->geom.pgsz == 4096) {
702 		ns->options |= OPT_PAGE4096;
703 	} else {
704 		NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
705 		return -EIO;
706 	}
707 
708 	if (ns->options & OPT_SMALLPAGE) {
709 		if (ns->geom.totsz <= (32 << 20)) {
710 			ns->geom.pgaddrbytes  = 3;
711 			ns->geom.secaddrbytes = 2;
712 		} else {
713 			ns->geom.pgaddrbytes  = 4;
714 			ns->geom.secaddrbytes = 3;
715 		}
716 	} else {
717 		if (ns->geom.totsz <= (128 << 20)) {
718 			ns->geom.pgaddrbytes  = 4;
719 			ns->geom.secaddrbytes = 2;
720 		} else {
721 			ns->geom.pgaddrbytes  = 5;
722 			ns->geom.secaddrbytes = 3;
723 		}
724 	}
725 
726 	/* Fill the partition_info structure */
727 	if (parts_num > ARRAY_SIZE(ns->partitions)) {
728 		NS_ERR("too many partitions.\n");
729 		ret = -EINVAL;
730 		goto error;
731 	}
732 	remains = ns->geom.totsz;
733 	next_offset = 0;
734 	for (i = 0; i < parts_num; ++i) {
735 		uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
736 
737 		if (!part_sz || part_sz > remains) {
738 			NS_ERR("bad partition size.\n");
739 			ret = -EINVAL;
740 			goto error;
741 		}
742 		ns->partitions[i].name   = get_partition_name(i);
743 		ns->partitions[i].offset = next_offset;
744 		ns->partitions[i].size   = part_sz;
745 		next_offset += ns->partitions[i].size;
746 		remains -= ns->partitions[i].size;
747 	}
748 	ns->nbparts = parts_num;
749 	if (remains) {
750 		if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
751 			NS_ERR("too many partitions.\n");
752 			ret = -EINVAL;
753 			goto error;
754 		}
755 		ns->partitions[i].name   = get_partition_name(i);
756 		ns->partitions[i].offset = next_offset;
757 		ns->partitions[i].size   = remains;
758 		ns->nbparts += 1;
759 	}
760 
761 	if (ns->busw == 16)
762 		NS_WARN("16-bit flashes support wasn't tested\n");
763 
764 	printk("flash size: %llu MiB\n",
765 			(unsigned long long)ns->geom.totsz >> 20);
766 	printk("page size: %u bytes\n",         ns->geom.pgsz);
767 	printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
768 	printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
769 	printk("pages number: %u\n",            ns->geom.pgnum);
770 	printk("pages per sector: %u\n",        ns->geom.pgsec);
771 	printk("bus width: %u\n",               ns->busw);
772 	printk("bits in sector size: %u\n",     ns->geom.secshift);
773 	printk("bits in page size: %u\n",       ns->geom.pgshift);
774 	printk("bits in OOB size: %u\n",	ffs(ns->geom.oobsz) - 1);
775 	printk("flash size with OOB: %llu KiB\n",
776 			(unsigned long long)ns->geom.totszoob >> 10);
777 	printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
778 	printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
779 	printk("options: %#x\n",                ns->options);
780 
781 	if ((ret = alloc_device(ns)) != 0)
782 		goto error;
783 
784 	/* Allocate / initialize the internal buffer */
785 	ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
786 	if (!ns->buf.byte) {
787 		NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
788 			ns->geom.pgszoob);
789 		ret = -ENOMEM;
790 		goto error;
791 	}
792 	memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
793 
794 	return 0;
795 
796 error:
797 	free_device(ns);
798 
799 	return ret;
800 }
801 
802 /*
803  * Free the nandsim structure.
804  */
free_nandsim(struct nandsim * ns)805 static void free_nandsim(struct nandsim *ns)
806 {
807 	kfree(ns->buf.byte);
808 	free_device(ns);
809 
810 	return;
811 }
812 
parse_badblocks(struct nandsim * ns,struct mtd_info * mtd)813 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
814 {
815 	char *w;
816 	int zero_ok;
817 	unsigned int erase_block_no;
818 	loff_t offset;
819 
820 	if (!badblocks)
821 		return 0;
822 	w = badblocks;
823 	do {
824 		zero_ok = (*w == '0' ? 1 : 0);
825 		erase_block_no = simple_strtoul(w, &w, 0);
826 		if (!zero_ok && !erase_block_no) {
827 			NS_ERR("invalid badblocks.\n");
828 			return -EINVAL;
829 		}
830 		offset = (loff_t)erase_block_no * ns->geom.secsz;
831 		if (mtd_block_markbad(mtd, offset)) {
832 			NS_ERR("invalid badblocks.\n");
833 			return -EINVAL;
834 		}
835 		if (*w == ',')
836 			w += 1;
837 	} while (*w);
838 	return 0;
839 }
840 
parse_weakblocks(void)841 static int parse_weakblocks(void)
842 {
843 	char *w;
844 	int zero_ok;
845 	unsigned int erase_block_no;
846 	unsigned int max_erases;
847 	struct weak_block *wb;
848 
849 	if (!weakblocks)
850 		return 0;
851 	w = weakblocks;
852 	do {
853 		zero_ok = (*w == '0' ? 1 : 0);
854 		erase_block_no = simple_strtoul(w, &w, 0);
855 		if (!zero_ok && !erase_block_no) {
856 			NS_ERR("invalid weakblocks.\n");
857 			return -EINVAL;
858 		}
859 		max_erases = 3;
860 		if (*w == ':') {
861 			w += 1;
862 			max_erases = simple_strtoul(w, &w, 0);
863 		}
864 		if (*w == ',')
865 			w += 1;
866 		wb = kzalloc(sizeof(*wb), GFP_KERNEL);
867 		if (!wb) {
868 			NS_ERR("unable to allocate memory.\n");
869 			return -ENOMEM;
870 		}
871 		wb->erase_block_no = erase_block_no;
872 		wb->max_erases = max_erases;
873 		list_add(&wb->list, &weak_blocks);
874 	} while (*w);
875 	return 0;
876 }
877 
erase_error(unsigned int erase_block_no)878 static int erase_error(unsigned int erase_block_no)
879 {
880 	struct weak_block *wb;
881 
882 	list_for_each_entry(wb, &weak_blocks, list)
883 		if (wb->erase_block_no == erase_block_no) {
884 			if (wb->erases_done >= wb->max_erases)
885 				return 1;
886 			wb->erases_done += 1;
887 			return 0;
888 		}
889 	return 0;
890 }
891 
parse_weakpages(void)892 static int parse_weakpages(void)
893 {
894 	char *w;
895 	int zero_ok;
896 	unsigned int page_no;
897 	unsigned int max_writes;
898 	struct weak_page *wp;
899 
900 	if (!weakpages)
901 		return 0;
902 	w = weakpages;
903 	do {
904 		zero_ok = (*w == '0' ? 1 : 0);
905 		page_no = simple_strtoul(w, &w, 0);
906 		if (!zero_ok && !page_no) {
907 			NS_ERR("invalid weakpagess.\n");
908 			return -EINVAL;
909 		}
910 		max_writes = 3;
911 		if (*w == ':') {
912 			w += 1;
913 			max_writes = simple_strtoul(w, &w, 0);
914 		}
915 		if (*w == ',')
916 			w += 1;
917 		wp = kzalloc(sizeof(*wp), GFP_KERNEL);
918 		if (!wp) {
919 			NS_ERR("unable to allocate memory.\n");
920 			return -ENOMEM;
921 		}
922 		wp->page_no = page_no;
923 		wp->max_writes = max_writes;
924 		list_add(&wp->list, &weak_pages);
925 	} while (*w);
926 	return 0;
927 }
928 
write_error(unsigned int page_no)929 static int write_error(unsigned int page_no)
930 {
931 	struct weak_page *wp;
932 
933 	list_for_each_entry(wp, &weak_pages, list)
934 		if (wp->page_no == page_no) {
935 			if (wp->writes_done >= wp->max_writes)
936 				return 1;
937 			wp->writes_done += 1;
938 			return 0;
939 		}
940 	return 0;
941 }
942 
parse_gravepages(void)943 static int parse_gravepages(void)
944 {
945 	char *g;
946 	int zero_ok;
947 	unsigned int page_no;
948 	unsigned int max_reads;
949 	struct grave_page *gp;
950 
951 	if (!gravepages)
952 		return 0;
953 	g = gravepages;
954 	do {
955 		zero_ok = (*g == '0' ? 1 : 0);
956 		page_no = simple_strtoul(g, &g, 0);
957 		if (!zero_ok && !page_no) {
958 			NS_ERR("invalid gravepagess.\n");
959 			return -EINVAL;
960 		}
961 		max_reads = 3;
962 		if (*g == ':') {
963 			g += 1;
964 			max_reads = simple_strtoul(g, &g, 0);
965 		}
966 		if (*g == ',')
967 			g += 1;
968 		gp = kzalloc(sizeof(*gp), GFP_KERNEL);
969 		if (!gp) {
970 			NS_ERR("unable to allocate memory.\n");
971 			return -ENOMEM;
972 		}
973 		gp->page_no = page_no;
974 		gp->max_reads = max_reads;
975 		list_add(&gp->list, &grave_pages);
976 	} while (*g);
977 	return 0;
978 }
979 
read_error(unsigned int page_no)980 static int read_error(unsigned int page_no)
981 {
982 	struct grave_page *gp;
983 
984 	list_for_each_entry(gp, &grave_pages, list)
985 		if (gp->page_no == page_no) {
986 			if (gp->reads_done >= gp->max_reads)
987 				return 1;
988 			gp->reads_done += 1;
989 			return 0;
990 		}
991 	return 0;
992 }
993 
free_lists(void)994 static void free_lists(void)
995 {
996 	struct list_head *pos, *n;
997 	list_for_each_safe(pos, n, &weak_blocks) {
998 		list_del(pos);
999 		kfree(list_entry(pos, struct weak_block, list));
1000 	}
1001 	list_for_each_safe(pos, n, &weak_pages) {
1002 		list_del(pos);
1003 		kfree(list_entry(pos, struct weak_page, list));
1004 	}
1005 	list_for_each_safe(pos, n, &grave_pages) {
1006 		list_del(pos);
1007 		kfree(list_entry(pos, struct grave_page, list));
1008 	}
1009 	kfree(erase_block_wear);
1010 }
1011 
setup_wear_reporting(struct mtd_info * mtd)1012 static int setup_wear_reporting(struct mtd_info *mtd)
1013 {
1014 	size_t mem;
1015 
1016 	wear_eb_count = div_u64(mtd->size, mtd->erasesize);
1017 	mem = wear_eb_count * sizeof(unsigned long);
1018 	if (mem / sizeof(unsigned long) != wear_eb_count) {
1019 		NS_ERR("Too many erase blocks for wear reporting\n");
1020 		return -ENOMEM;
1021 	}
1022 	erase_block_wear = kzalloc(mem, GFP_KERNEL);
1023 	if (!erase_block_wear) {
1024 		NS_ERR("Too many erase blocks for wear reporting\n");
1025 		return -ENOMEM;
1026 	}
1027 	return 0;
1028 }
1029 
update_wear(unsigned int erase_block_no)1030 static void update_wear(unsigned int erase_block_no)
1031 {
1032 	if (!erase_block_wear)
1033 		return;
1034 	total_wear += 1;
1035 	/*
1036 	 * TODO: Notify this through a debugfs entry,
1037 	 * instead of showing an error message.
1038 	 */
1039 	if (total_wear == 0)
1040 		NS_ERR("Erase counter total overflow\n");
1041 	erase_block_wear[erase_block_no] += 1;
1042 	if (erase_block_wear[erase_block_no] == 0)
1043 		NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1044 }
1045 
1046 /*
1047  * Returns the string representation of 'state' state.
1048  */
get_state_name(uint32_t state)1049 static char *get_state_name(uint32_t state)
1050 {
1051 	switch (NS_STATE(state)) {
1052 		case STATE_CMD_READ0:
1053 			return "STATE_CMD_READ0";
1054 		case STATE_CMD_READ1:
1055 			return "STATE_CMD_READ1";
1056 		case STATE_CMD_PAGEPROG:
1057 			return "STATE_CMD_PAGEPROG";
1058 		case STATE_CMD_READOOB:
1059 			return "STATE_CMD_READOOB";
1060 		case STATE_CMD_READSTART:
1061 			return "STATE_CMD_READSTART";
1062 		case STATE_CMD_ERASE1:
1063 			return "STATE_CMD_ERASE1";
1064 		case STATE_CMD_STATUS:
1065 			return "STATE_CMD_STATUS";
1066 		case STATE_CMD_SEQIN:
1067 			return "STATE_CMD_SEQIN";
1068 		case STATE_CMD_READID:
1069 			return "STATE_CMD_READID";
1070 		case STATE_CMD_ERASE2:
1071 			return "STATE_CMD_ERASE2";
1072 		case STATE_CMD_RESET:
1073 			return "STATE_CMD_RESET";
1074 		case STATE_CMD_RNDOUT:
1075 			return "STATE_CMD_RNDOUT";
1076 		case STATE_CMD_RNDOUTSTART:
1077 			return "STATE_CMD_RNDOUTSTART";
1078 		case STATE_ADDR_PAGE:
1079 			return "STATE_ADDR_PAGE";
1080 		case STATE_ADDR_SEC:
1081 			return "STATE_ADDR_SEC";
1082 		case STATE_ADDR_ZERO:
1083 			return "STATE_ADDR_ZERO";
1084 		case STATE_ADDR_COLUMN:
1085 			return "STATE_ADDR_COLUMN";
1086 		case STATE_DATAIN:
1087 			return "STATE_DATAIN";
1088 		case STATE_DATAOUT:
1089 			return "STATE_DATAOUT";
1090 		case STATE_DATAOUT_ID:
1091 			return "STATE_DATAOUT_ID";
1092 		case STATE_DATAOUT_STATUS:
1093 			return "STATE_DATAOUT_STATUS";
1094 		case STATE_DATAOUT_STATUS_M:
1095 			return "STATE_DATAOUT_STATUS_M";
1096 		case STATE_READY:
1097 			return "STATE_READY";
1098 		case STATE_UNKNOWN:
1099 			return "STATE_UNKNOWN";
1100 	}
1101 
1102 	NS_ERR("get_state_name: unknown state, BUG\n");
1103 	return NULL;
1104 }
1105 
1106 /*
1107  * Check if command is valid.
1108  *
1109  * RETURNS: 1 if wrong command, 0 if right.
1110  */
check_command(int cmd)1111 static int check_command(int cmd)
1112 {
1113 	switch (cmd) {
1114 
1115 	case NAND_CMD_READ0:
1116 	case NAND_CMD_READ1:
1117 	case NAND_CMD_READSTART:
1118 	case NAND_CMD_PAGEPROG:
1119 	case NAND_CMD_READOOB:
1120 	case NAND_CMD_ERASE1:
1121 	case NAND_CMD_STATUS:
1122 	case NAND_CMD_SEQIN:
1123 	case NAND_CMD_READID:
1124 	case NAND_CMD_ERASE2:
1125 	case NAND_CMD_RESET:
1126 	case NAND_CMD_RNDOUT:
1127 	case NAND_CMD_RNDOUTSTART:
1128 		return 0;
1129 
1130 	default:
1131 		return 1;
1132 	}
1133 }
1134 
1135 /*
1136  * Returns state after command is accepted by command number.
1137  */
get_state_by_command(unsigned command)1138 static uint32_t get_state_by_command(unsigned command)
1139 {
1140 	switch (command) {
1141 		case NAND_CMD_READ0:
1142 			return STATE_CMD_READ0;
1143 		case NAND_CMD_READ1:
1144 			return STATE_CMD_READ1;
1145 		case NAND_CMD_PAGEPROG:
1146 			return STATE_CMD_PAGEPROG;
1147 		case NAND_CMD_READSTART:
1148 			return STATE_CMD_READSTART;
1149 		case NAND_CMD_READOOB:
1150 			return STATE_CMD_READOOB;
1151 		case NAND_CMD_ERASE1:
1152 			return STATE_CMD_ERASE1;
1153 		case NAND_CMD_STATUS:
1154 			return STATE_CMD_STATUS;
1155 		case NAND_CMD_SEQIN:
1156 			return STATE_CMD_SEQIN;
1157 		case NAND_CMD_READID:
1158 			return STATE_CMD_READID;
1159 		case NAND_CMD_ERASE2:
1160 			return STATE_CMD_ERASE2;
1161 		case NAND_CMD_RESET:
1162 			return STATE_CMD_RESET;
1163 		case NAND_CMD_RNDOUT:
1164 			return STATE_CMD_RNDOUT;
1165 		case NAND_CMD_RNDOUTSTART:
1166 			return STATE_CMD_RNDOUTSTART;
1167 	}
1168 
1169 	NS_ERR("get_state_by_command: unknown command, BUG\n");
1170 	return 0;
1171 }
1172 
1173 /*
1174  * Move an address byte to the correspondent internal register.
1175  */
accept_addr_byte(struct nandsim * ns,u_char bt)1176 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1177 {
1178 	uint byte = (uint)bt;
1179 
1180 	if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1181 		ns->regs.column |= (byte << 8 * ns->regs.count);
1182 	else {
1183 		ns->regs.row |= (byte << 8 * (ns->regs.count -
1184 						ns->geom.pgaddrbytes +
1185 						ns->geom.secaddrbytes));
1186 	}
1187 
1188 	return;
1189 }
1190 
1191 /*
1192  * Switch to STATE_READY state.
1193  */
switch_to_ready_state(struct nandsim * ns,u_char status)1194 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1195 {
1196 	NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1197 
1198 	ns->state       = STATE_READY;
1199 	ns->nxstate     = STATE_UNKNOWN;
1200 	ns->op          = NULL;
1201 	ns->npstates    = 0;
1202 	ns->stateidx    = 0;
1203 	ns->regs.num    = 0;
1204 	ns->regs.count  = 0;
1205 	ns->regs.off    = 0;
1206 	ns->regs.row    = 0;
1207 	ns->regs.column = 0;
1208 	ns->regs.status = status;
1209 }
1210 
1211 /*
1212  * If the operation isn't known yet, try to find it in the global array
1213  * of supported operations.
1214  *
1215  * Operation can be unknown because of the following.
1216  *   1. New command was accepted and this is the first call to find the
1217  *      correspondent states chain. In this case ns->npstates = 0;
1218  *   2. There are several operations which begin with the same command(s)
1219  *      (for example program from the second half and read from the
1220  *      second half operations both begin with the READ1 command). In this
1221  *      case the ns->pstates[] array contains previous states.
1222  *
1223  * Thus, the function tries to find operation containing the following
1224  * states (if the 'flag' parameter is 0):
1225  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1226  *
1227  * If (one and only one) matching operation is found, it is accepted (
1228  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1229  * zeroed).
1230  *
1231  * If there are several matches, the current state is pushed to the
1232  * ns->pstates.
1233  *
1234  * The operation can be unknown only while commands are input to the chip.
1235  * As soon as address command is accepted, the operation must be known.
1236  * In such situation the function is called with 'flag' != 0, and the
1237  * operation is searched using the following pattern:
1238  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1239  *
1240  * It is supposed that this pattern must either match one operation or
1241  * none. There can't be ambiguity in that case.
1242  *
1243  * If no matches found, the function does the following:
1244  *   1. if there are saved states present, try to ignore them and search
1245  *      again only using the last command. If nothing was found, switch
1246  *      to the STATE_READY state.
1247  *   2. if there are no saved states, switch to the STATE_READY state.
1248  *
1249  * RETURNS: -2 - no matched operations found.
1250  *          -1 - several matches.
1251  *           0 - operation is found.
1252  */
find_operation(struct nandsim * ns,uint32_t flag)1253 static int find_operation(struct nandsim *ns, uint32_t flag)
1254 {
1255 	int opsfound = 0;
1256 	int i, j, idx = 0;
1257 
1258 	for (i = 0; i < NS_OPER_NUM; i++) {
1259 
1260 		int found = 1;
1261 
1262 		if (!(ns->options & ops[i].reqopts))
1263 			/* Ignore operations we can't perform */
1264 			continue;
1265 
1266 		if (flag) {
1267 			if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1268 				continue;
1269 		} else {
1270 			if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1271 				continue;
1272 		}
1273 
1274 		for (j = 0; j < ns->npstates; j++)
1275 			if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1276 				&& (ns->options & ops[idx].reqopts)) {
1277 				found = 0;
1278 				break;
1279 			}
1280 
1281 		if (found) {
1282 			idx = i;
1283 			opsfound += 1;
1284 		}
1285 	}
1286 
1287 	if (opsfound == 1) {
1288 		/* Exact match */
1289 		ns->op = &ops[idx].states[0];
1290 		if (flag) {
1291 			/*
1292 			 * In this case the find_operation function was
1293 			 * called when address has just began input. But it isn't
1294 			 * yet fully input and the current state must
1295 			 * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1296 			 * state must be the next state (ns->nxstate).
1297 			 */
1298 			ns->stateidx = ns->npstates - 1;
1299 		} else {
1300 			ns->stateidx = ns->npstates;
1301 		}
1302 		ns->npstates = 0;
1303 		ns->state = ns->op[ns->stateidx];
1304 		ns->nxstate = ns->op[ns->stateidx + 1];
1305 		NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1306 				idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1307 		return 0;
1308 	}
1309 
1310 	if (opsfound == 0) {
1311 		/* Nothing was found. Try to ignore previous commands (if any) and search again */
1312 		if (ns->npstates != 0) {
1313 			NS_DBG("find_operation: no operation found, try again with state %s\n",
1314 					get_state_name(ns->state));
1315 			ns->npstates = 0;
1316 			return find_operation(ns, 0);
1317 
1318 		}
1319 		NS_DBG("find_operation: no operations found\n");
1320 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1321 		return -2;
1322 	}
1323 
1324 	if (flag) {
1325 		/* This shouldn't happen */
1326 		NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1327 		return -2;
1328 	}
1329 
1330 	NS_DBG("find_operation: there is still ambiguity\n");
1331 
1332 	ns->pstates[ns->npstates++] = ns->state;
1333 
1334 	return -1;
1335 }
1336 
put_pages(struct nandsim * ns)1337 static void put_pages(struct nandsim *ns)
1338 {
1339 	int i;
1340 
1341 	for (i = 0; i < ns->held_cnt; i++)
1342 		page_cache_release(ns->held_pages[i]);
1343 }
1344 
1345 /* Get page cache pages in advance to provide NOFS memory allocation */
get_pages(struct nandsim * ns,struct file * file,size_t count,loff_t pos)1346 static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos)
1347 {
1348 	pgoff_t index, start_index, end_index;
1349 	struct page *page;
1350 	struct address_space *mapping = file->f_mapping;
1351 
1352 	start_index = pos >> PAGE_CACHE_SHIFT;
1353 	end_index = (pos + count - 1) >> PAGE_CACHE_SHIFT;
1354 	if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1355 		return -EINVAL;
1356 	ns->held_cnt = 0;
1357 	for (index = start_index; index <= end_index; index++) {
1358 		page = find_get_page(mapping, index);
1359 		if (page == NULL) {
1360 			page = find_or_create_page(mapping, index, GFP_NOFS);
1361 			if (page == NULL) {
1362 				write_inode_now(mapping->host, 1);
1363 				page = find_or_create_page(mapping, index, GFP_NOFS);
1364 			}
1365 			if (page == NULL) {
1366 				put_pages(ns);
1367 				return -ENOMEM;
1368 			}
1369 			unlock_page(page);
1370 		}
1371 		ns->held_pages[ns->held_cnt++] = page;
1372 	}
1373 	return 0;
1374 }
1375 
set_memalloc(void)1376 static int set_memalloc(void)
1377 {
1378 	if (current->flags & PF_MEMALLOC)
1379 		return 0;
1380 	current->flags |= PF_MEMALLOC;
1381 	return 1;
1382 }
1383 
clear_memalloc(int memalloc)1384 static void clear_memalloc(int memalloc)
1385 {
1386 	if (memalloc)
1387 		current->flags &= ~PF_MEMALLOC;
1388 }
1389 
read_file(struct nandsim * ns,struct file * file,void * buf,size_t count,loff_t pos)1390 static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1391 {
1392 	ssize_t tx;
1393 	int err, memalloc;
1394 
1395 	err = get_pages(ns, file, count, pos);
1396 	if (err)
1397 		return err;
1398 	memalloc = set_memalloc();
1399 	tx = kernel_read(file, pos, buf, count);
1400 	clear_memalloc(memalloc);
1401 	put_pages(ns);
1402 	return tx;
1403 }
1404 
write_file(struct nandsim * ns,struct file * file,void * buf,size_t count,loff_t pos)1405 static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1406 {
1407 	ssize_t tx;
1408 	int err, memalloc;
1409 
1410 	err = get_pages(ns, file, count, pos);
1411 	if (err)
1412 		return err;
1413 	memalloc = set_memalloc();
1414 	tx = kernel_write(file, buf, count, pos);
1415 	clear_memalloc(memalloc);
1416 	put_pages(ns);
1417 	return tx;
1418 }
1419 
1420 /*
1421  * Returns a pointer to the current page.
1422  */
NS_GET_PAGE(struct nandsim * ns)1423 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1424 {
1425 	return &(ns->pages[ns->regs.row]);
1426 }
1427 
1428 /*
1429  * Retuns a pointer to the current byte, within the current page.
1430  */
NS_PAGE_BYTE_OFF(struct nandsim * ns)1431 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1432 {
1433 	return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1434 }
1435 
do_read_error(struct nandsim * ns,int num)1436 static int do_read_error(struct nandsim *ns, int num)
1437 {
1438 	unsigned int page_no = ns->regs.row;
1439 
1440 	if (read_error(page_no)) {
1441 		prandom_bytes(ns->buf.byte, num);
1442 		NS_WARN("simulating read error in page %u\n", page_no);
1443 		return 1;
1444 	}
1445 	return 0;
1446 }
1447 
do_bit_flips(struct nandsim * ns,int num)1448 static void do_bit_flips(struct nandsim *ns, int num)
1449 {
1450 	if (bitflips && prandom_u32() < (1 << 22)) {
1451 		int flips = 1;
1452 		if (bitflips > 1)
1453 			flips = (prandom_u32() % (int) bitflips) + 1;
1454 		while (flips--) {
1455 			int pos = prandom_u32() % (num * 8);
1456 			ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1457 			NS_WARN("read_page: flipping bit %d in page %d "
1458 				"reading from %d ecc: corrected=%u failed=%u\n",
1459 				pos, ns->regs.row, ns->regs.column + ns->regs.off,
1460 				nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1461 		}
1462 	}
1463 }
1464 
1465 /*
1466  * Fill the NAND buffer with data read from the specified page.
1467  */
read_page(struct nandsim * ns,int num)1468 static void read_page(struct nandsim *ns, int num)
1469 {
1470 	union ns_mem *mypage;
1471 
1472 	if (ns->cfile) {
1473 		if (!test_bit(ns->regs.row, ns->pages_written)) {
1474 			NS_DBG("read_page: page %d not written\n", ns->regs.row);
1475 			memset(ns->buf.byte, 0xFF, num);
1476 		} else {
1477 			loff_t pos;
1478 			ssize_t tx;
1479 
1480 			NS_DBG("read_page: page %d written, reading from %d\n",
1481 				ns->regs.row, ns->regs.column + ns->regs.off);
1482 			if (do_read_error(ns, num))
1483 				return;
1484 			pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1485 			tx = read_file(ns, ns->cfile, ns->buf.byte, num, pos);
1486 			if (tx != num) {
1487 				NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1488 				return;
1489 			}
1490 			do_bit_flips(ns, num);
1491 		}
1492 		return;
1493 	}
1494 
1495 	mypage = NS_GET_PAGE(ns);
1496 	if (mypage->byte == NULL) {
1497 		NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1498 		memset(ns->buf.byte, 0xFF, num);
1499 	} else {
1500 		NS_DBG("read_page: page %d allocated, reading from %d\n",
1501 			ns->regs.row, ns->regs.column + ns->regs.off);
1502 		if (do_read_error(ns, num))
1503 			return;
1504 		memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1505 		do_bit_flips(ns, num);
1506 	}
1507 }
1508 
1509 /*
1510  * Erase all pages in the specified sector.
1511  */
erase_sector(struct nandsim * ns)1512 static void erase_sector(struct nandsim *ns)
1513 {
1514 	union ns_mem *mypage;
1515 	int i;
1516 
1517 	if (ns->cfile) {
1518 		for (i = 0; i < ns->geom.pgsec; i++)
1519 			if (__test_and_clear_bit(ns->regs.row + i,
1520 						 ns->pages_written)) {
1521 				NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1522 			}
1523 		return;
1524 	}
1525 
1526 	mypage = NS_GET_PAGE(ns);
1527 	for (i = 0; i < ns->geom.pgsec; i++) {
1528 		if (mypage->byte != NULL) {
1529 			NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1530 			kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1531 			mypage->byte = NULL;
1532 		}
1533 		mypage++;
1534 	}
1535 }
1536 
1537 /*
1538  * Program the specified page with the contents from the NAND buffer.
1539  */
prog_page(struct nandsim * ns,int num)1540 static int prog_page(struct nandsim *ns, int num)
1541 {
1542 	int i;
1543 	union ns_mem *mypage;
1544 	u_char *pg_off;
1545 
1546 	if (ns->cfile) {
1547 		loff_t off;
1548 		ssize_t tx;
1549 		int all;
1550 
1551 		NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1552 		pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1553 		off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1554 		if (!test_bit(ns->regs.row, ns->pages_written)) {
1555 			all = 1;
1556 			memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1557 		} else {
1558 			all = 0;
1559 			tx = read_file(ns, ns->cfile, pg_off, num, off);
1560 			if (tx != num) {
1561 				NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1562 				return -1;
1563 			}
1564 		}
1565 		for (i = 0; i < num; i++)
1566 			pg_off[i] &= ns->buf.byte[i];
1567 		if (all) {
1568 			loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1569 			tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, pos);
1570 			if (tx != ns->geom.pgszoob) {
1571 				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1572 				return -1;
1573 			}
1574 			__set_bit(ns->regs.row, ns->pages_written);
1575 		} else {
1576 			tx = write_file(ns, ns->cfile, pg_off, num, off);
1577 			if (tx != num) {
1578 				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1579 				return -1;
1580 			}
1581 		}
1582 		return 0;
1583 	}
1584 
1585 	mypage = NS_GET_PAGE(ns);
1586 	if (mypage->byte == NULL) {
1587 		NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1588 		/*
1589 		 * We allocate memory with GFP_NOFS because a flash FS may
1590 		 * utilize this. If it is holding an FS lock, then gets here,
1591 		 * then kernel memory alloc runs writeback which goes to the FS
1592 		 * again and deadlocks. This was seen in practice.
1593 		 */
1594 		mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1595 		if (mypage->byte == NULL) {
1596 			NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1597 			return -1;
1598 		}
1599 		memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1600 	}
1601 
1602 	pg_off = NS_PAGE_BYTE_OFF(ns);
1603 	for (i = 0; i < num; i++)
1604 		pg_off[i] &= ns->buf.byte[i];
1605 
1606 	return 0;
1607 }
1608 
1609 /*
1610  * If state has any action bit, perform this action.
1611  *
1612  * RETURNS: 0 if success, -1 if error.
1613  */
do_state_action(struct nandsim * ns,uint32_t action)1614 static int do_state_action(struct nandsim *ns, uint32_t action)
1615 {
1616 	int num;
1617 	int busdiv = ns->busw == 8 ? 1 : 2;
1618 	unsigned int erase_block_no, page_no;
1619 
1620 	action &= ACTION_MASK;
1621 
1622 	/* Check that page address input is correct */
1623 	if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1624 		NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1625 		return -1;
1626 	}
1627 
1628 	switch (action) {
1629 
1630 	case ACTION_CPY:
1631 		/*
1632 		 * Copy page data to the internal buffer.
1633 		 */
1634 
1635 		/* Column shouldn't be very large */
1636 		if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1637 			NS_ERR("do_state_action: column number is too large\n");
1638 			break;
1639 		}
1640 		num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1641 		read_page(ns, num);
1642 
1643 		NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1644 			num, NS_RAW_OFFSET(ns) + ns->regs.off);
1645 
1646 		if (ns->regs.off == 0)
1647 			NS_LOG("read page %d\n", ns->regs.row);
1648 		else if (ns->regs.off < ns->geom.pgsz)
1649 			NS_LOG("read page %d (second half)\n", ns->regs.row);
1650 		else
1651 			NS_LOG("read OOB of page %d\n", ns->regs.row);
1652 
1653 		NS_UDELAY(access_delay);
1654 		NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1655 
1656 		break;
1657 
1658 	case ACTION_SECERASE:
1659 		/*
1660 		 * Erase sector.
1661 		 */
1662 
1663 		if (ns->lines.wp) {
1664 			NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1665 			return -1;
1666 		}
1667 
1668 		if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1669 			|| (ns->regs.row & ~(ns->geom.secsz - 1))) {
1670 			NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1671 			return -1;
1672 		}
1673 
1674 		ns->regs.row = (ns->regs.row <<
1675 				8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1676 		ns->regs.column = 0;
1677 
1678 		erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1679 
1680 		NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1681 				ns->regs.row, NS_RAW_OFFSET(ns));
1682 		NS_LOG("erase sector %u\n", erase_block_no);
1683 
1684 		erase_sector(ns);
1685 
1686 		NS_MDELAY(erase_delay);
1687 
1688 		if (erase_block_wear)
1689 			update_wear(erase_block_no);
1690 
1691 		if (erase_error(erase_block_no)) {
1692 			NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1693 			return -1;
1694 		}
1695 
1696 		break;
1697 
1698 	case ACTION_PRGPAGE:
1699 		/*
1700 		 * Program page - move internal buffer data to the page.
1701 		 */
1702 
1703 		if (ns->lines.wp) {
1704 			NS_WARN("do_state_action: device is write-protected, programm\n");
1705 			return -1;
1706 		}
1707 
1708 		num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1709 		if (num != ns->regs.count) {
1710 			NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1711 					ns->regs.count, num);
1712 			return -1;
1713 		}
1714 
1715 		if (prog_page(ns, num) == -1)
1716 			return -1;
1717 
1718 		page_no = ns->regs.row;
1719 
1720 		NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1721 			num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1722 		NS_LOG("programm page %d\n", ns->regs.row);
1723 
1724 		NS_UDELAY(programm_delay);
1725 		NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1726 
1727 		if (write_error(page_no)) {
1728 			NS_WARN("simulating write failure in page %u\n", page_no);
1729 			return -1;
1730 		}
1731 
1732 		break;
1733 
1734 	case ACTION_ZEROOFF:
1735 		NS_DBG("do_state_action: set internal offset to 0\n");
1736 		ns->regs.off = 0;
1737 		break;
1738 
1739 	case ACTION_HALFOFF:
1740 		if (!(ns->options & OPT_PAGE512_8BIT)) {
1741 			NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1742 				"byte page size 8x chips\n");
1743 			return -1;
1744 		}
1745 		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1746 		ns->regs.off = ns->geom.pgsz/2;
1747 		break;
1748 
1749 	case ACTION_OOBOFF:
1750 		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1751 		ns->regs.off = ns->geom.pgsz;
1752 		break;
1753 
1754 	default:
1755 		NS_DBG("do_state_action: BUG! unknown action\n");
1756 	}
1757 
1758 	return 0;
1759 }
1760 
1761 /*
1762  * Switch simulator's state.
1763  */
switch_state(struct nandsim * ns)1764 static void switch_state(struct nandsim *ns)
1765 {
1766 	if (ns->op) {
1767 		/*
1768 		 * The current operation have already been identified.
1769 		 * Just follow the states chain.
1770 		 */
1771 
1772 		ns->stateidx += 1;
1773 		ns->state = ns->nxstate;
1774 		ns->nxstate = ns->op[ns->stateidx + 1];
1775 
1776 		NS_DBG("switch_state: operation is known, switch to the next state, "
1777 			"state: %s, nxstate: %s\n",
1778 			get_state_name(ns->state), get_state_name(ns->nxstate));
1779 
1780 		/* See, whether we need to do some action */
1781 		if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1782 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1783 			return;
1784 		}
1785 
1786 	} else {
1787 		/*
1788 		 * We don't yet know which operation we perform.
1789 		 * Try to identify it.
1790 		 */
1791 
1792 		/*
1793 		 *  The only event causing the switch_state function to
1794 		 *  be called with yet unknown operation is new command.
1795 		 */
1796 		ns->state = get_state_by_command(ns->regs.command);
1797 
1798 		NS_DBG("switch_state: operation is unknown, try to find it\n");
1799 
1800 		if (find_operation(ns, 0) != 0)
1801 			return;
1802 
1803 		if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1804 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1805 			return;
1806 		}
1807 	}
1808 
1809 	/* For 16x devices column means the page offset in words */
1810 	if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1811 		NS_DBG("switch_state: double the column number for 16x device\n");
1812 		ns->regs.column <<= 1;
1813 	}
1814 
1815 	if (NS_STATE(ns->nxstate) == STATE_READY) {
1816 		/*
1817 		 * The current state is the last. Return to STATE_READY
1818 		 */
1819 
1820 		u_char status = NS_STATUS_OK(ns);
1821 
1822 		/* In case of data states, see if all bytes were input/output */
1823 		if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1824 			&& ns->regs.count != ns->regs.num) {
1825 			NS_WARN("switch_state: not all bytes were processed, %d left\n",
1826 					ns->regs.num - ns->regs.count);
1827 			status = NS_STATUS_FAILED(ns);
1828 		}
1829 
1830 		NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1831 
1832 		switch_to_ready_state(ns, status);
1833 
1834 		return;
1835 	} else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1836 		/*
1837 		 * If the next state is data input/output, switch to it now
1838 		 */
1839 
1840 		ns->state      = ns->nxstate;
1841 		ns->nxstate    = ns->op[++ns->stateidx + 1];
1842 		ns->regs.num   = ns->regs.count = 0;
1843 
1844 		NS_DBG("switch_state: the next state is data I/O, switch, "
1845 			"state: %s, nxstate: %s\n",
1846 			get_state_name(ns->state), get_state_name(ns->nxstate));
1847 
1848 		/*
1849 		 * Set the internal register to the count of bytes which
1850 		 * are expected to be input or output
1851 		 */
1852 		switch (NS_STATE(ns->state)) {
1853 			case STATE_DATAIN:
1854 			case STATE_DATAOUT:
1855 				ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1856 				break;
1857 
1858 			case STATE_DATAOUT_ID:
1859 				ns->regs.num = ns->geom.idbytes;
1860 				break;
1861 
1862 			case STATE_DATAOUT_STATUS:
1863 			case STATE_DATAOUT_STATUS_M:
1864 				ns->regs.count = ns->regs.num = 0;
1865 				break;
1866 
1867 			default:
1868 				NS_ERR("switch_state: BUG! unknown data state\n");
1869 		}
1870 
1871 	} else if (ns->nxstate & STATE_ADDR_MASK) {
1872 		/*
1873 		 * If the next state is address input, set the internal
1874 		 * register to the number of expected address bytes
1875 		 */
1876 
1877 		ns->regs.count = 0;
1878 
1879 		switch (NS_STATE(ns->nxstate)) {
1880 			case STATE_ADDR_PAGE:
1881 				ns->regs.num = ns->geom.pgaddrbytes;
1882 
1883 				break;
1884 			case STATE_ADDR_SEC:
1885 				ns->regs.num = ns->geom.secaddrbytes;
1886 				break;
1887 
1888 			case STATE_ADDR_ZERO:
1889 				ns->regs.num = 1;
1890 				break;
1891 
1892 			case STATE_ADDR_COLUMN:
1893 				/* Column address is always 2 bytes */
1894 				ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1895 				break;
1896 
1897 			default:
1898 				NS_ERR("switch_state: BUG! unknown address state\n");
1899 		}
1900 	} else {
1901 		/*
1902 		 * Just reset internal counters.
1903 		 */
1904 
1905 		ns->regs.num = 0;
1906 		ns->regs.count = 0;
1907 	}
1908 }
1909 
ns_nand_read_byte(struct mtd_info * mtd)1910 static u_char ns_nand_read_byte(struct mtd_info *mtd)
1911 {
1912 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1913 	u_char outb = 0x00;
1914 
1915 	/* Sanity and correctness checks */
1916 	if (!ns->lines.ce) {
1917 		NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1918 		return outb;
1919 	}
1920 	if (ns->lines.ale || ns->lines.cle) {
1921 		NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1922 		return outb;
1923 	}
1924 	if (!(ns->state & STATE_DATAOUT_MASK)) {
1925 		NS_WARN("read_byte: unexpected data output cycle, state is %s "
1926 			"return %#x\n", get_state_name(ns->state), (uint)outb);
1927 		return outb;
1928 	}
1929 
1930 	/* Status register may be read as many times as it is wanted */
1931 	if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1932 		NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1933 		return ns->regs.status;
1934 	}
1935 
1936 	/* Check if there is any data in the internal buffer which may be read */
1937 	if (ns->regs.count == ns->regs.num) {
1938 		NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1939 		return outb;
1940 	}
1941 
1942 	switch (NS_STATE(ns->state)) {
1943 		case STATE_DATAOUT:
1944 			if (ns->busw == 8) {
1945 				outb = ns->buf.byte[ns->regs.count];
1946 				ns->regs.count += 1;
1947 			} else {
1948 				outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1949 				ns->regs.count += 2;
1950 			}
1951 			break;
1952 		case STATE_DATAOUT_ID:
1953 			NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1954 			outb = ns->ids[ns->regs.count];
1955 			ns->regs.count += 1;
1956 			break;
1957 		default:
1958 			BUG();
1959 	}
1960 
1961 	if (ns->regs.count == ns->regs.num) {
1962 		NS_DBG("read_byte: all bytes were read\n");
1963 
1964 		if (NS_STATE(ns->nxstate) == STATE_READY)
1965 			switch_state(ns);
1966 	}
1967 
1968 	return outb;
1969 }
1970 
ns_nand_write_byte(struct mtd_info * mtd,u_char byte)1971 static void ns_nand_write_byte(struct mtd_info *mtd, u_char byte)
1972 {
1973 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
1974 
1975 	/* Sanity and correctness checks */
1976 	if (!ns->lines.ce) {
1977 		NS_ERR("write_byte: chip is disabled, ignore write\n");
1978 		return;
1979 	}
1980 	if (ns->lines.ale && ns->lines.cle) {
1981 		NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1982 		return;
1983 	}
1984 
1985 	if (ns->lines.cle == 1) {
1986 		/*
1987 		 * The byte written is a command.
1988 		 */
1989 
1990 		if (byte == NAND_CMD_RESET) {
1991 			NS_LOG("reset chip\n");
1992 			switch_to_ready_state(ns, NS_STATUS_OK(ns));
1993 			return;
1994 		}
1995 
1996 		/* Check that the command byte is correct */
1997 		if (check_command(byte)) {
1998 			NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1999 			return;
2000 		}
2001 
2002 		if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
2003 			|| NS_STATE(ns->state) == STATE_DATAOUT_STATUS_M
2004 			|| NS_STATE(ns->state) == STATE_DATAOUT) {
2005 			int row = ns->regs.row;
2006 
2007 			switch_state(ns);
2008 			if (byte == NAND_CMD_RNDOUT)
2009 				ns->regs.row = row;
2010 		}
2011 
2012 		/* Check if chip is expecting command */
2013 		if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
2014 			/* Do not warn if only 2 id bytes are read */
2015 			if (!(ns->regs.command == NAND_CMD_READID &&
2016 			    NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
2017 				/*
2018 				 * We are in situation when something else (not command)
2019 				 * was expected but command was input. In this case ignore
2020 				 * previous command(s)/state(s) and accept the last one.
2021 				 */
2022 				NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
2023 					"ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
2024 			}
2025 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2026 		}
2027 
2028 		NS_DBG("command byte corresponding to %s state accepted\n",
2029 			get_state_name(get_state_by_command(byte)));
2030 		ns->regs.command = byte;
2031 		switch_state(ns);
2032 
2033 	} else if (ns->lines.ale == 1) {
2034 		/*
2035 		 * The byte written is an address.
2036 		 */
2037 
2038 		if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
2039 
2040 			NS_DBG("write_byte: operation isn't known yet, identify it\n");
2041 
2042 			if (find_operation(ns, 1) < 0)
2043 				return;
2044 
2045 			if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
2046 				switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2047 				return;
2048 			}
2049 
2050 			ns->regs.count = 0;
2051 			switch (NS_STATE(ns->nxstate)) {
2052 				case STATE_ADDR_PAGE:
2053 					ns->regs.num = ns->geom.pgaddrbytes;
2054 					break;
2055 				case STATE_ADDR_SEC:
2056 					ns->regs.num = ns->geom.secaddrbytes;
2057 					break;
2058 				case STATE_ADDR_ZERO:
2059 					ns->regs.num = 1;
2060 					break;
2061 				default:
2062 					BUG();
2063 			}
2064 		}
2065 
2066 		/* Check that chip is expecting address */
2067 		if (!(ns->nxstate & STATE_ADDR_MASK)) {
2068 			NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
2069 				"switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
2070 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2071 			return;
2072 		}
2073 
2074 		/* Check if this is expected byte */
2075 		if (ns->regs.count == ns->regs.num) {
2076 			NS_ERR("write_byte: no more address bytes expected\n");
2077 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2078 			return;
2079 		}
2080 
2081 		accept_addr_byte(ns, byte);
2082 
2083 		ns->regs.count += 1;
2084 
2085 		NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2086 				(uint)byte, ns->regs.count, ns->regs.num);
2087 
2088 		if (ns->regs.count == ns->regs.num) {
2089 			NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2090 			switch_state(ns);
2091 		}
2092 
2093 	} else {
2094 		/*
2095 		 * The byte written is an input data.
2096 		 */
2097 
2098 		/* Check that chip is expecting data input */
2099 		if (!(ns->state & STATE_DATAIN_MASK)) {
2100 			NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
2101 				"switch to %s\n", (uint)byte,
2102 				get_state_name(ns->state), get_state_name(STATE_READY));
2103 			switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2104 			return;
2105 		}
2106 
2107 		/* Check if this is expected byte */
2108 		if (ns->regs.count == ns->regs.num) {
2109 			NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2110 					ns->regs.num);
2111 			return;
2112 		}
2113 
2114 		if (ns->busw == 8) {
2115 			ns->buf.byte[ns->regs.count] = byte;
2116 			ns->regs.count += 1;
2117 		} else {
2118 			ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2119 			ns->regs.count += 2;
2120 		}
2121 	}
2122 
2123 	return;
2124 }
2125 
ns_hwcontrol(struct mtd_info * mtd,int cmd,unsigned int bitmask)2126 static void ns_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int bitmask)
2127 {
2128 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2129 
2130 	ns->lines.cle = bitmask & NAND_CLE ? 1 : 0;
2131 	ns->lines.ale = bitmask & NAND_ALE ? 1 : 0;
2132 	ns->lines.ce = bitmask & NAND_NCE ? 1 : 0;
2133 
2134 	if (cmd != NAND_CMD_NONE)
2135 		ns_nand_write_byte(mtd, cmd);
2136 }
2137 
ns_device_ready(struct mtd_info * mtd)2138 static int ns_device_ready(struct mtd_info *mtd)
2139 {
2140 	NS_DBG("device_ready\n");
2141 	return 1;
2142 }
2143 
ns_nand_read_word(struct mtd_info * mtd)2144 static uint16_t ns_nand_read_word(struct mtd_info *mtd)
2145 {
2146 	struct nand_chip *chip = (struct nand_chip *)mtd->priv;
2147 
2148 	NS_DBG("read_word\n");
2149 
2150 	return chip->read_byte(mtd) | (chip->read_byte(mtd) << 8);
2151 }
2152 
ns_nand_write_buf(struct mtd_info * mtd,const u_char * buf,int len)2153 static void ns_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
2154 {
2155 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2156 
2157 	/* Check that chip is expecting data input */
2158 	if (!(ns->state & STATE_DATAIN_MASK)) {
2159 		NS_ERR("write_buf: data input isn't expected, state is %s, "
2160 			"switch to STATE_READY\n", get_state_name(ns->state));
2161 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2162 		return;
2163 	}
2164 
2165 	/* Check if these are expected bytes */
2166 	if (ns->regs.count + len > ns->regs.num) {
2167 		NS_ERR("write_buf: too many input bytes\n");
2168 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2169 		return;
2170 	}
2171 
2172 	memcpy(ns->buf.byte + ns->regs.count, buf, len);
2173 	ns->regs.count += len;
2174 
2175 	if (ns->regs.count == ns->regs.num) {
2176 		NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2177 	}
2178 }
2179 
ns_nand_read_buf(struct mtd_info * mtd,u_char * buf,int len)2180 static void ns_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
2181 {
2182 	struct nandsim *ns = ((struct nand_chip *)mtd->priv)->priv;
2183 
2184 	/* Sanity and correctness checks */
2185 	if (!ns->lines.ce) {
2186 		NS_ERR("read_buf: chip is disabled\n");
2187 		return;
2188 	}
2189 	if (ns->lines.ale || ns->lines.cle) {
2190 		NS_ERR("read_buf: ALE or CLE pin is high\n");
2191 		return;
2192 	}
2193 	if (!(ns->state & STATE_DATAOUT_MASK)) {
2194 		NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2195 			get_state_name(ns->state));
2196 		return;
2197 	}
2198 
2199 	if (NS_STATE(ns->state) != STATE_DATAOUT) {
2200 		int i;
2201 
2202 		for (i = 0; i < len; i++)
2203 			buf[i] = ((struct nand_chip *)mtd->priv)->read_byte(mtd);
2204 
2205 		return;
2206 	}
2207 
2208 	/* Check if these are expected bytes */
2209 	if (ns->regs.count + len > ns->regs.num) {
2210 		NS_ERR("read_buf: too many bytes to read\n");
2211 		switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2212 		return;
2213 	}
2214 
2215 	memcpy(buf, ns->buf.byte + ns->regs.count, len);
2216 	ns->regs.count += len;
2217 
2218 	if (ns->regs.count == ns->regs.num) {
2219 		if (NS_STATE(ns->nxstate) == STATE_READY)
2220 			switch_state(ns);
2221 	}
2222 
2223 	return;
2224 }
2225 
2226 /*
2227  * Module initialization function
2228  */
ns_init_module(void)2229 static int __init ns_init_module(void)
2230 {
2231 	struct nand_chip *chip;
2232 	struct nandsim *nand;
2233 	int retval = -ENOMEM, i;
2234 
2235 	if (bus_width != 8 && bus_width != 16) {
2236 		NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2237 		return -EINVAL;
2238 	}
2239 
2240 	/* Allocate and initialize mtd_info, nand_chip and nandsim structures */
2241 	nsmtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip)
2242 				+ sizeof(struct nandsim), GFP_KERNEL);
2243 	if (!nsmtd) {
2244 		NS_ERR("unable to allocate core structures.\n");
2245 		return -ENOMEM;
2246 	}
2247 	chip        = (struct nand_chip *)(nsmtd + 1);
2248         nsmtd->priv = (void *)chip;
2249 	nand        = (struct nandsim *)(chip + 1);
2250 	chip->priv  = (void *)nand;
2251 
2252 	/*
2253 	 * Register simulator's callbacks.
2254 	 */
2255 	chip->cmd_ctrl	 = ns_hwcontrol;
2256 	chip->read_byte  = ns_nand_read_byte;
2257 	chip->dev_ready  = ns_device_ready;
2258 	chip->write_buf  = ns_nand_write_buf;
2259 	chip->read_buf   = ns_nand_read_buf;
2260 	chip->read_word  = ns_nand_read_word;
2261 	chip->ecc.mode   = NAND_ECC_SOFT;
2262 	/* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2263 	/* and 'badblocks' parameters to work */
2264 	chip->options   |= NAND_SKIP_BBTSCAN;
2265 
2266 	switch (bbt) {
2267 	case 2:
2268 		 chip->bbt_options |= NAND_BBT_NO_OOB;
2269 	case 1:
2270 		 chip->bbt_options |= NAND_BBT_USE_FLASH;
2271 	case 0:
2272 		break;
2273 	default:
2274 		NS_ERR("bbt has to be 0..2\n");
2275 		retval = -EINVAL;
2276 		goto error;
2277 	}
2278 	/*
2279 	 * Perform minimum nandsim structure initialization to handle
2280 	 * the initial ID read command correctly
2281 	 */
2282 	if (third_id_byte != 0xFF || fourth_id_byte != 0xFF)
2283 		nand->geom.idbytes = 4;
2284 	else
2285 		nand->geom.idbytes = 2;
2286 	nand->regs.status = NS_STATUS_OK(nand);
2287 	nand->nxstate = STATE_UNKNOWN;
2288 	nand->options |= OPT_PAGE512; /* temporary value */
2289 	nand->ids[0] = first_id_byte;
2290 	nand->ids[1] = second_id_byte;
2291 	nand->ids[2] = third_id_byte;
2292 	nand->ids[3] = fourth_id_byte;
2293 	if (bus_width == 16) {
2294 		nand->busw = 16;
2295 		chip->options |= NAND_BUSWIDTH_16;
2296 	}
2297 
2298 	nsmtd->owner = THIS_MODULE;
2299 
2300 	if ((retval = parse_weakblocks()) != 0)
2301 		goto error;
2302 
2303 	if ((retval = parse_weakpages()) != 0)
2304 		goto error;
2305 
2306 	if ((retval = parse_gravepages()) != 0)
2307 		goto error;
2308 
2309 	retval = nand_scan_ident(nsmtd, 1, NULL);
2310 	if (retval) {
2311 		NS_ERR("cannot scan NAND Simulator device\n");
2312 		if (retval > 0)
2313 			retval = -ENXIO;
2314 		goto error;
2315 	}
2316 
2317 	if (bch) {
2318 		unsigned int eccsteps, eccbytes;
2319 		if (!mtd_nand_has_bch()) {
2320 			NS_ERR("BCH ECC support is disabled\n");
2321 			retval = -EINVAL;
2322 			goto error;
2323 		}
2324 		/* use 512-byte ecc blocks */
2325 		eccsteps = nsmtd->writesize/512;
2326 		eccbytes = (bch*13+7)/8;
2327 		/* do not bother supporting small page devices */
2328 		if ((nsmtd->oobsize < 64) || !eccsteps) {
2329 			NS_ERR("bch not available on small page devices\n");
2330 			retval = -EINVAL;
2331 			goto error;
2332 		}
2333 		if ((eccbytes*eccsteps+2) > nsmtd->oobsize) {
2334 			NS_ERR("invalid bch value %u\n", bch);
2335 			retval = -EINVAL;
2336 			goto error;
2337 		}
2338 		chip->ecc.mode = NAND_ECC_SOFT_BCH;
2339 		chip->ecc.size = 512;
2340 		chip->ecc.bytes = eccbytes;
2341 		NS_INFO("using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2342 	}
2343 
2344 	retval = nand_scan_tail(nsmtd);
2345 	if (retval) {
2346 		NS_ERR("can't register NAND Simulator\n");
2347 		if (retval > 0)
2348 			retval = -ENXIO;
2349 		goto error;
2350 	}
2351 
2352 	if (overridesize) {
2353 		uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2354 		if (new_size >> overridesize != nsmtd->erasesize) {
2355 			NS_ERR("overridesize is too big\n");
2356 			retval = -EINVAL;
2357 			goto err_exit;
2358 		}
2359 		/* N.B. This relies on nand_scan not doing anything with the size before we change it */
2360 		nsmtd->size = new_size;
2361 		chip->chipsize = new_size;
2362 		chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2363 		chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2364 	}
2365 
2366 	if ((retval = setup_wear_reporting(nsmtd)) != 0)
2367 		goto err_exit;
2368 
2369 	if ((retval = nandsim_debugfs_create(nand)) != 0)
2370 		goto err_exit;
2371 
2372 	if ((retval = init_nandsim(nsmtd)) != 0)
2373 		goto err_exit;
2374 
2375 	if ((retval = chip->scan_bbt(nsmtd)) != 0)
2376 		goto err_exit;
2377 
2378 	if ((retval = parse_badblocks(nand, nsmtd)) != 0)
2379 		goto err_exit;
2380 
2381 	/* Register NAND partitions */
2382 	retval = mtd_device_register(nsmtd, &nand->partitions[0],
2383 				     nand->nbparts);
2384 	if (retval != 0)
2385 		goto err_exit;
2386 
2387         return 0;
2388 
2389 err_exit:
2390 	free_nandsim(nand);
2391 	nand_release(nsmtd);
2392 	for (i = 0;i < ARRAY_SIZE(nand->partitions); ++i)
2393 		kfree(nand->partitions[i].name);
2394 error:
2395 	kfree(nsmtd);
2396 	free_lists();
2397 
2398 	return retval;
2399 }
2400 
2401 module_init(ns_init_module);
2402 
2403 /*
2404  * Module clean-up function
2405  */
ns_cleanup_module(void)2406 static void __exit ns_cleanup_module(void)
2407 {
2408 	struct nandsim *ns = ((struct nand_chip *)nsmtd->priv)->priv;
2409 	int i;
2410 
2411 	nandsim_debugfs_remove(ns);
2412 	free_nandsim(ns);    /* Free nandsim private resources */
2413 	nand_release(nsmtd); /* Unregister driver */
2414 	for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2415 		kfree(ns->partitions[i].name);
2416 	kfree(nsmtd);        /* Free other structures */
2417 	free_lists();
2418 }
2419 
2420 module_exit(ns_cleanup_module);
2421 
2422 MODULE_LICENSE ("GPL");
2423 MODULE_AUTHOR ("Artem B. Bityuckiy");
2424 MODULE_DESCRIPTION ("The NAND flash simulator");
2425