1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * NAND flash simulator.
4  *
5  * Author: Artem B. Bityuckiy <dedekind@oktetlabs.ru>, <dedekind@infradead.org>
6  *
7  * Copyright (C) 2004 Nokia Corporation
8  *
9  * Note: NS means "NAND Simulator".
10  * Note: Input means input TO flash chip, output means output FROM chip.
11  */
12 
13 #define pr_fmt(fmt)  "[nandsim]" fmt
14 
15 #include <linux/init.h>
16 #include <linux/types.h>
17 #include <linux/module.h>
18 #include <linux/moduleparam.h>
19 #include <linux/vmalloc.h>
20 #include <linux/math64.h>
21 #include <linux/slab.h>
22 #include <linux/errno.h>
23 #include <linux/string.h>
24 #include <linux/mtd/mtd.h>
25 #include <linux/mtd/rawnand.h>
26 #include <linux/mtd/partitions.h>
27 #include <linux/delay.h>
28 #include <linux/list.h>
29 #include <linux/random.h>
30 #include <linux/sched.h>
31 #include <linux/sched/mm.h>
32 #include <linux/fs.h>
33 #include <linux/pagemap.h>
34 #include <linux/seq_file.h>
35 #include <linux/debugfs.h>
36 
37 /* Default simulator parameters values */
38 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
39     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
40     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
41     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
42 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
43 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
44 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
45 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
46 #endif
47 
48 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
49 #define CONFIG_NANDSIM_ACCESS_DELAY 25
50 #endif
51 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
52 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
53 #endif
54 #ifndef CONFIG_NANDSIM_ERASE_DELAY
55 #define CONFIG_NANDSIM_ERASE_DELAY 2
56 #endif
57 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
58 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
59 #endif
60 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
61 #define CONFIG_NANDSIM_INPUT_CYCLE  50
62 #endif
63 #ifndef CONFIG_NANDSIM_BUS_WIDTH
64 #define CONFIG_NANDSIM_BUS_WIDTH  8
65 #endif
66 #ifndef CONFIG_NANDSIM_DO_DELAYS
67 #define CONFIG_NANDSIM_DO_DELAYS  0
68 #endif
69 #ifndef CONFIG_NANDSIM_LOG
70 #define CONFIG_NANDSIM_LOG        0
71 #endif
72 #ifndef CONFIG_NANDSIM_DBG
73 #define CONFIG_NANDSIM_DBG        0
74 #endif
75 #ifndef CONFIG_NANDSIM_MAX_PARTS
76 #define CONFIG_NANDSIM_MAX_PARTS  32
77 #endif
78 
79 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
80 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
81 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
82 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
83 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
84 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
85 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
86 static uint log            = CONFIG_NANDSIM_LOG;
87 static uint dbg            = CONFIG_NANDSIM_DBG;
88 static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];
89 static unsigned int parts_num;
90 static char *badblocks = NULL;
91 static char *weakblocks = NULL;
92 static char *weakpages = NULL;
93 static unsigned int bitflips = 0;
94 static char *gravepages = NULL;
95 static unsigned int overridesize = 0;
96 static char *cache_file = NULL;
97 static unsigned int bbt;
98 static unsigned int bch;
99 static u_char id_bytes[8] = {
100 	[0] = CONFIG_NANDSIM_FIRST_ID_BYTE,
101 	[1] = CONFIG_NANDSIM_SECOND_ID_BYTE,
102 	[2] = CONFIG_NANDSIM_THIRD_ID_BYTE,
103 	[3] = CONFIG_NANDSIM_FOURTH_ID_BYTE,
104 	[4 ... 7] = 0xFF,
105 };
106 
107 module_param_array(id_bytes, byte, NULL, 0400);
108 module_param_named(first_id_byte, id_bytes[0], byte, 0400);
109 module_param_named(second_id_byte, id_bytes[1], byte, 0400);
110 module_param_named(third_id_byte, id_bytes[2], byte, 0400);
111 module_param_named(fourth_id_byte, id_bytes[3], byte, 0400);
112 module_param(access_delay,   uint, 0400);
113 module_param(programm_delay, uint, 0400);
114 module_param(erase_delay,    uint, 0400);
115 module_param(output_cycle,   uint, 0400);
116 module_param(input_cycle,    uint, 0400);
117 module_param(bus_width,      uint, 0400);
118 module_param(do_delays,      uint, 0400);
119 module_param(log,            uint, 0400);
120 module_param(dbg,            uint, 0400);
121 module_param_array(parts, ulong, &parts_num, 0400);
122 module_param(badblocks,      charp, 0400);
123 module_param(weakblocks,     charp, 0400);
124 module_param(weakpages,      charp, 0400);
125 module_param(bitflips,       uint, 0400);
126 module_param(gravepages,     charp, 0400);
127 module_param(overridesize,   uint, 0400);
128 module_param(cache_file,     charp, 0400);
129 module_param(bbt,	     uint, 0400);
130 module_param(bch,	     uint, 0400);
131 
132 MODULE_PARM_DESC(id_bytes,       "The ID bytes returned by NAND Flash 'read ID' command");
133 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID) (obsolete)");
134 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID) (obsolete)");
135 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command (obsolete)");
136 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command (obsolete)");
137 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");
138 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
139 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
140 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");
141 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");
142 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
143 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
144 MODULE_PARM_DESC(log,            "Perform logging if not zero");
145 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
146 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
147 /* Page and erase block positions for the following parameters are independent of any partitions */
148 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
149 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
150 				 " separated by commas e.g. 113:2 means eb 113"
151 				 " can be erased only twice before failing");
152 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
153 				 " separated by commas e.g. 1401:2 means page 1401"
154 				 " can be written only twice before failing");
155 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
156 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
157 				 " separated by commas e.g. 1401:2 means page 1401"
158 				 " can be read only twice before failing");
159 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
160 				 "The size is specified in erase blocks and as the exponent of a power of two"
161 				 " e.g. 5 means a size of 32 erase blocks");
162 MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");
163 MODULE_PARM_DESC(bbt,		 "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");
164 MODULE_PARM_DESC(bch,		 "Enable BCH ecc and set how many bits should "
165 				 "be correctable in 512-byte blocks");
166 
167 /* The largest possible page size */
168 #define NS_LARGEST_PAGE_SIZE	4096
169 
170 /* Simulator's output macros (logging, debugging, warning, error) */
171 #define NS_LOG(args...) \
172 	do { if (log) pr_debug(" log: " args); } while(0)
173 #define NS_DBG(args...) \
174 	do { if (dbg) pr_debug(" debug: " args); } while(0)
175 #define NS_WARN(args...) \
176 	do { pr_warn(" warning: " args); } while(0)
177 #define NS_ERR(args...) \
178 	do { pr_err(" error: " args); } while(0)
179 #define NS_INFO(args...) \
180 	do { pr_info(" " args); } while(0)
181 
182 /* Busy-wait delay macros (microseconds, milliseconds) */
183 #define NS_UDELAY(us) \
184         do { if (do_delays) udelay(us); } while(0)
185 #define NS_MDELAY(us) \
186         do { if (do_delays) mdelay(us); } while(0)
187 
188 /* Is the nandsim structure initialized ? */
189 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
190 
191 /* Good operation completion status */
192 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
193 
194 /* Operation failed completion status */
195 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
196 
197 /* Calculate the page offset in flash RAM image by (row, column) address */
198 #define NS_RAW_OFFSET(ns) \
199 	(((ns)->regs.row * (ns)->geom.pgszoob) + (ns)->regs.column)
200 
201 /* Calculate the OOB offset in flash RAM image by (row, column) address */
202 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
203 
204 /* After a command is input, the simulator goes to one of the following states */
205 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
206 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
207 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
208 #define STATE_CMD_PAGEPROG     0x00000004 /* start page program */
209 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
210 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
211 #define STATE_CMD_STATUS       0x00000007 /* read status */
212 #define STATE_CMD_SEQIN        0x00000009 /* sequential data input */
213 #define STATE_CMD_READID       0x0000000A /* read ID */
214 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
215 #define STATE_CMD_RESET        0x0000000C /* reset */
216 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
217 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
218 #define STATE_CMD_MASK         0x0000000F /* command states mask */
219 
220 /* After an address is input, the simulator goes to one of these states */
221 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
222 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
223 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
224 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
225 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
226 
227 /* During data input/output the simulator is in these states */
228 #define STATE_DATAIN           0x00000100 /* waiting for data input */
229 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
230 
231 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
232 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
233 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
234 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
235 
236 /* Previous operation is done, ready to accept new requests */
237 #define STATE_READY            0x00000000
238 
239 /* This state is used to mark that the next state isn't known yet */
240 #define STATE_UNKNOWN          0x10000000
241 
242 /* Simulator's actions bit masks */
243 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
244 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
245 #define ACTION_SECERASE  0x00300000 /* erase sector */
246 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
247 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
248 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
249 #define ACTION_MASK      0x00700000 /* action mask */
250 
251 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
252 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
253 
254 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
255 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
256 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
257 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
258 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
259 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
260 #define OPT_SMALLPAGE    (OPT_PAGE512) /* 512-byte page chips */
261 
262 /* Remove action bits from state */
263 #define NS_STATE(x) ((x) & ~ACTION_MASK)
264 
265 /*
266  * Maximum previous states which need to be saved. Currently saving is
267  * only needed for page program operation with preceded read command
268  * (which is only valid for 512-byte pages).
269  */
270 #define NS_MAX_PREVSTATES 1
271 
272 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
273 #define NS_MAX_HELD_PAGES 16
274 
275 /*
276  * A union to represent flash memory contents and flash buffer.
277  */
278 union ns_mem {
279 	u_char *byte;    /* for byte access */
280 	uint16_t *word;  /* for 16-bit word access */
281 };
282 
283 /*
284  * The structure which describes all the internal simulator data.
285  */
286 struct nandsim {
287 	struct nand_chip chip;
288 	struct nand_controller base;
289 	struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
290 	unsigned int nbparts;
291 
292 	uint busw;              /* flash chip bus width (8 or 16) */
293 	u_char ids[8];          /* chip's ID bytes */
294 	uint32_t options;       /* chip's characteristic bits */
295 	uint32_t state;         /* current chip state */
296 	uint32_t nxstate;       /* next expected state */
297 
298 	uint32_t *op;           /* current operation, NULL operations isn't known yet  */
299 	uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
300 	uint16_t npstates;      /* number of previous states saved */
301 	uint16_t stateidx;      /* current state index */
302 
303 	/* The simulated NAND flash pages array */
304 	union ns_mem *pages;
305 
306 	/* Slab allocator for nand pages */
307 	struct kmem_cache *nand_pages_slab;
308 
309 	/* Internal buffer of page + OOB size bytes */
310 	union ns_mem buf;
311 
312 	/* NAND flash "geometry" */
313 	struct {
314 		uint64_t totsz;     /* total flash size, bytes */
315 		uint32_t secsz;     /* flash sector (erase block) size, bytes */
316 		uint pgsz;          /* NAND flash page size, bytes */
317 		uint oobsz;         /* page OOB area size, bytes */
318 		uint64_t totszoob;  /* total flash size including OOB, bytes */
319 		uint pgszoob;       /* page size including OOB , bytes*/
320 		uint secszoob;      /* sector size including OOB, bytes */
321 		uint pgnum;         /* total number of pages */
322 		uint pgsec;         /* number of pages per sector */
323 		uint secshift;      /* bits number in sector size */
324 		uint pgshift;       /* bits number in page size */
325 		uint pgaddrbytes;   /* bytes per page address */
326 		uint secaddrbytes;  /* bytes per sector address */
327 		uint idbytes;       /* the number ID bytes that this chip outputs */
328 	} geom;
329 
330 	/* NAND flash internal registers */
331 	struct {
332 		unsigned command; /* the command register */
333 		u_char   status;  /* the status register */
334 		uint     row;     /* the page number */
335 		uint     column;  /* the offset within page */
336 		uint     count;   /* internal counter */
337 		uint     num;     /* number of bytes which must be processed */
338 		uint     off;     /* fixed page offset */
339 	} regs;
340 
341 	/* NAND flash lines state */
342         struct {
343                 int ce;  /* chip Enable */
344                 int cle; /* command Latch Enable */
345                 int ale; /* address Latch Enable */
346                 int wp;  /* write Protect */
347         } lines;
348 
349 	/* Fields needed when using a cache file */
350 	struct file *cfile; /* Open file */
351 	unsigned long *pages_written; /* Which pages have been written */
352 	void *file_buf;
353 	struct page *held_pages[NS_MAX_HELD_PAGES];
354 	int held_cnt;
355 
356 	/* debugfs entry */
357 	struct dentry *dent;
358 };
359 
360 /*
361  * Operations array. To perform any operation the simulator must pass
362  * through the correspondent states chain.
363  */
364 static struct nandsim_operations {
365 	uint32_t reqopts;  /* options which are required to perform the operation */
366 	uint32_t states[NS_OPER_STATES]; /* operation's states */
367 } ops[NS_OPER_NUM] = {
368 	/* Read page + OOB from the beginning */
369 	{OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
370 			STATE_DATAOUT, STATE_READY}},
371 	/* Read page + OOB from the second half */
372 	{OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
373 			STATE_DATAOUT, STATE_READY}},
374 	/* Read OOB */
375 	{OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
376 			STATE_DATAOUT, STATE_READY}},
377 	/* Program page starting from the beginning */
378 	{OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
379 			STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
380 	/* Program page starting from the beginning */
381 	{OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
382 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
383 	/* Program page starting from the second half */
384 	{OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
385 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
386 	/* Program OOB */
387 	{OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
388 			      STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
389 	/* Erase sector */
390 	{OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
391 	/* Read status */
392 	{OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
393 	/* Read ID */
394 	{OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
395 	/* Large page devices read page */
396 	{OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
397 			       STATE_DATAOUT, STATE_READY}},
398 	/* Large page devices random page read */
399 	{OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
400 			       STATE_DATAOUT, STATE_READY}},
401 };
402 
403 struct weak_block {
404 	struct list_head list;
405 	unsigned int erase_block_no;
406 	unsigned int max_erases;
407 	unsigned int erases_done;
408 };
409 
410 static LIST_HEAD(weak_blocks);
411 
412 struct weak_page {
413 	struct list_head list;
414 	unsigned int page_no;
415 	unsigned int max_writes;
416 	unsigned int writes_done;
417 };
418 
419 static LIST_HEAD(weak_pages);
420 
421 struct grave_page {
422 	struct list_head list;
423 	unsigned int page_no;
424 	unsigned int max_reads;
425 	unsigned int reads_done;
426 };
427 
428 static LIST_HEAD(grave_pages);
429 
430 static unsigned long *erase_block_wear = NULL;
431 static unsigned int wear_eb_count = 0;
432 static unsigned long total_wear = 0;
433 
434 /* MTD structure for NAND controller */
435 static struct mtd_info *nsmtd;
436 
ns_show(struct seq_file * m,void * private)437 static int ns_show(struct seq_file *m, void *private)
438 {
439 	unsigned long wmin = -1, wmax = 0, avg;
440 	unsigned long deciles[10], decile_max[10], tot = 0;
441 	unsigned int i;
442 
443 	/* Calc wear stats */
444 	for (i = 0; i < wear_eb_count; ++i) {
445 		unsigned long wear = erase_block_wear[i];
446 		if (wear < wmin)
447 			wmin = wear;
448 		if (wear > wmax)
449 			wmax = wear;
450 		tot += wear;
451 	}
452 
453 	for (i = 0; i < 9; ++i) {
454 		deciles[i] = 0;
455 		decile_max[i] = (wmax * (i + 1) + 5) / 10;
456 	}
457 	deciles[9] = 0;
458 	decile_max[9] = wmax;
459 	for (i = 0; i < wear_eb_count; ++i) {
460 		int d;
461 		unsigned long wear = erase_block_wear[i];
462 		for (d = 0; d < 10; ++d)
463 			if (wear <= decile_max[d]) {
464 				deciles[d] += 1;
465 				break;
466 			}
467 	}
468 	avg = tot / wear_eb_count;
469 
470 	/* Output wear report */
471 	seq_printf(m, "Total numbers of erases:  %lu\n", tot);
472 	seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);
473 	seq_printf(m, "Average number of erases: %lu\n", avg);
474 	seq_printf(m, "Maximum number of erases: %lu\n", wmax);
475 	seq_printf(m, "Minimum number of erases: %lu\n", wmin);
476 	for (i = 0; i < 10; ++i) {
477 		unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
478 		if (from > decile_max[i])
479 			continue;
480 		seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
481 			from,
482 			decile_max[i],
483 			deciles[i]);
484 	}
485 
486 	return 0;
487 }
488 DEFINE_SHOW_ATTRIBUTE(ns);
489 
490 /**
491  * ns_debugfs_create - initialize debugfs
492  * @ns: nandsim device description object
493  *
494  * This function creates all debugfs files for UBI device @ubi. Returns zero in
495  * case of success and a negative error code in case of failure.
496  */
ns_debugfs_create(struct nandsim * ns)497 static int ns_debugfs_create(struct nandsim *ns)
498 {
499 	struct dentry *root = nsmtd->dbg.dfs_dir;
500 
501 	/*
502 	 * Just skip debugfs initialization when the debugfs directory is
503 	 * missing.
504 	 */
505 	if (IS_ERR_OR_NULL(root)) {
506 		if (IS_ENABLED(CONFIG_DEBUG_FS) &&
507 		    !IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
508 			NS_WARN("CONFIG_MTD_PARTITIONED_MASTER must be enabled to expose debugfs stuff\n");
509 		return 0;
510 	}
511 
512 	ns->dent = debugfs_create_file("nandsim_wear_report", 0400, root, ns,
513 				       &ns_fops);
514 	if (IS_ERR_OR_NULL(ns->dent)) {
515 		NS_ERR("cannot create \"nandsim_wear_report\" debugfs entry\n");
516 		return -1;
517 	}
518 
519 	return 0;
520 }
521 
ns_debugfs_remove(struct nandsim * ns)522 static void ns_debugfs_remove(struct nandsim *ns)
523 {
524 	debugfs_remove_recursive(ns->dent);
525 }
526 
527 /*
528  * Allocate array of page pointers, create slab allocation for an array
529  * and initialize the array by NULL pointers.
530  *
531  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
532  */
ns_alloc_device(struct nandsim * ns)533 static int __init ns_alloc_device(struct nandsim *ns)
534 {
535 	struct file *cfile;
536 	int i, err;
537 
538 	if (cache_file) {
539 		cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
540 		if (IS_ERR(cfile))
541 			return PTR_ERR(cfile);
542 		if (!(cfile->f_mode & FMODE_CAN_READ)) {
543 			NS_ERR("alloc_device: cache file not readable\n");
544 			err = -EINVAL;
545 			goto err_close_filp;
546 		}
547 		if (!(cfile->f_mode & FMODE_CAN_WRITE)) {
548 			NS_ERR("alloc_device: cache file not writeable\n");
549 			err = -EINVAL;
550 			goto err_close_filp;
551 		}
552 		ns->pages_written =
553 			vzalloc(array_size(sizeof(unsigned long),
554 					   BITS_TO_LONGS(ns->geom.pgnum)));
555 		if (!ns->pages_written) {
556 			NS_ERR("alloc_device: unable to allocate pages written array\n");
557 			err = -ENOMEM;
558 			goto err_close_filp;
559 		}
560 		ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
561 		if (!ns->file_buf) {
562 			NS_ERR("alloc_device: unable to allocate file buf\n");
563 			err = -ENOMEM;
564 			goto err_free_pw;
565 		}
566 		ns->cfile = cfile;
567 
568 		return 0;
569 
570 err_free_pw:
571 		vfree(ns->pages_written);
572 err_close_filp:
573 		filp_close(cfile, NULL);
574 
575 		return err;
576 	}
577 
578 	ns->pages = vmalloc(array_size(sizeof(union ns_mem), ns->geom.pgnum));
579 	if (!ns->pages) {
580 		NS_ERR("alloc_device: unable to allocate page array\n");
581 		return -ENOMEM;
582 	}
583 	for (i = 0; i < ns->geom.pgnum; i++) {
584 		ns->pages[i].byte = NULL;
585 	}
586 	ns->nand_pages_slab = kmem_cache_create("nandsim",
587 						ns->geom.pgszoob, 0, 0, NULL);
588 	if (!ns->nand_pages_slab) {
589 		NS_ERR("cache_create: unable to create kmem_cache\n");
590 		err = -ENOMEM;
591 		goto err_free_pg;
592 	}
593 
594 	return 0;
595 
596 err_free_pg:
597 	vfree(ns->pages);
598 
599 	return err;
600 }
601 
602 /*
603  * Free any allocated pages, and free the array of page pointers.
604  */
ns_free_device(struct nandsim * ns)605 static void ns_free_device(struct nandsim *ns)
606 {
607 	int i;
608 
609 	if (ns->cfile) {
610 		kfree(ns->file_buf);
611 		vfree(ns->pages_written);
612 		filp_close(ns->cfile, NULL);
613 		return;
614 	}
615 
616 	if (ns->pages) {
617 		for (i = 0; i < ns->geom.pgnum; i++) {
618 			if (ns->pages[i].byte)
619 				kmem_cache_free(ns->nand_pages_slab,
620 						ns->pages[i].byte);
621 		}
622 		kmem_cache_destroy(ns->nand_pages_slab);
623 		vfree(ns->pages);
624 	}
625 }
626 
ns_get_partition_name(int i)627 static char __init *ns_get_partition_name(int i)
628 {
629 	return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i);
630 }
631 
632 /*
633  * Initialize the nandsim structure.
634  *
635  * RETURNS: 0 if success, -ERRNO if failure.
636  */
ns_init(struct mtd_info * mtd)637 static int __init ns_init(struct mtd_info *mtd)
638 {
639 	struct nand_chip *chip = mtd_to_nand(mtd);
640 	struct nandsim   *ns   = nand_get_controller_data(chip);
641 	int i, ret = 0;
642 	uint64_t remains;
643 	uint64_t next_offset;
644 
645 	if (NS_IS_INITIALIZED(ns)) {
646 		NS_ERR("init_nandsim: nandsim is already initialized\n");
647 		return -EIO;
648 	}
649 
650 	/* Initialize the NAND flash parameters */
651 	ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
652 	ns->geom.totsz    = mtd->size;
653 	ns->geom.pgsz     = mtd->writesize;
654 	ns->geom.oobsz    = mtd->oobsize;
655 	ns->geom.secsz    = mtd->erasesize;
656 	ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
657 	ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
658 	ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
659 	ns->geom.secshift = ffs(ns->geom.secsz) - 1;
660 	ns->geom.pgshift  = chip->page_shift;
661 	ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
662 	ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
663 	ns->options = 0;
664 
665 	if (ns->geom.pgsz == 512) {
666 		ns->options |= OPT_PAGE512;
667 		if (ns->busw == 8)
668 			ns->options |= OPT_PAGE512_8BIT;
669 	} else if (ns->geom.pgsz == 2048) {
670 		ns->options |= OPT_PAGE2048;
671 	} else if (ns->geom.pgsz == 4096) {
672 		ns->options |= OPT_PAGE4096;
673 	} else {
674 		NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
675 		return -EIO;
676 	}
677 
678 	if (ns->options & OPT_SMALLPAGE) {
679 		if (ns->geom.totsz <= (32 << 20)) {
680 			ns->geom.pgaddrbytes  = 3;
681 			ns->geom.secaddrbytes = 2;
682 		} else {
683 			ns->geom.pgaddrbytes  = 4;
684 			ns->geom.secaddrbytes = 3;
685 		}
686 	} else {
687 		if (ns->geom.totsz <= (128 << 20)) {
688 			ns->geom.pgaddrbytes  = 4;
689 			ns->geom.secaddrbytes = 2;
690 		} else {
691 			ns->geom.pgaddrbytes  = 5;
692 			ns->geom.secaddrbytes = 3;
693 		}
694 	}
695 
696 	/* Fill the partition_info structure */
697 	if (parts_num > ARRAY_SIZE(ns->partitions)) {
698 		NS_ERR("too many partitions.\n");
699 		return -EINVAL;
700 	}
701 	remains = ns->geom.totsz;
702 	next_offset = 0;
703 	for (i = 0; i < parts_num; ++i) {
704 		uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
705 
706 		if (!part_sz || part_sz > remains) {
707 			NS_ERR("bad partition size.\n");
708 			return -EINVAL;
709 		}
710 		ns->partitions[i].name = ns_get_partition_name(i);
711 		if (!ns->partitions[i].name) {
712 			NS_ERR("unable to allocate memory.\n");
713 			return -ENOMEM;
714 		}
715 		ns->partitions[i].offset = next_offset;
716 		ns->partitions[i].size   = part_sz;
717 		next_offset += ns->partitions[i].size;
718 		remains -= ns->partitions[i].size;
719 	}
720 	ns->nbparts = parts_num;
721 	if (remains) {
722 		if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
723 			NS_ERR("too many partitions.\n");
724 			ret = -EINVAL;
725 			goto free_partition_names;
726 		}
727 		ns->partitions[i].name = ns_get_partition_name(i);
728 		if (!ns->partitions[i].name) {
729 			NS_ERR("unable to allocate memory.\n");
730 			ret = -ENOMEM;
731 			goto free_partition_names;
732 		}
733 		ns->partitions[i].offset = next_offset;
734 		ns->partitions[i].size   = remains;
735 		ns->nbparts += 1;
736 	}
737 
738 	if (ns->busw == 16)
739 		NS_WARN("16-bit flashes support wasn't tested\n");
740 
741 	printk("flash size: %llu MiB\n",
742 			(unsigned long long)ns->geom.totsz >> 20);
743 	printk("page size: %u bytes\n",         ns->geom.pgsz);
744 	printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
745 	printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
746 	printk("pages number: %u\n",            ns->geom.pgnum);
747 	printk("pages per sector: %u\n",        ns->geom.pgsec);
748 	printk("bus width: %u\n",               ns->busw);
749 	printk("bits in sector size: %u\n",     ns->geom.secshift);
750 	printk("bits in page size: %u\n",       ns->geom.pgshift);
751 	printk("bits in OOB size: %u\n",	ffs(ns->geom.oobsz) - 1);
752 	printk("flash size with OOB: %llu KiB\n",
753 			(unsigned long long)ns->geom.totszoob >> 10);
754 	printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
755 	printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
756 	printk("options: %#x\n",                ns->options);
757 
758 	ret = ns_alloc_device(ns);
759 	if (ret)
760 		goto free_partition_names;
761 
762 	/* Allocate / initialize the internal buffer */
763 	ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
764 	if (!ns->buf.byte) {
765 		NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
766 			ns->geom.pgszoob);
767 		ret = -ENOMEM;
768 		goto free_device;
769 	}
770 	memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
771 
772 	return 0;
773 
774 free_device:
775 	ns_free_device(ns);
776 free_partition_names:
777 	for (i = 0; i < ARRAY_SIZE(ns->partitions); ++i)
778 		kfree(ns->partitions[i].name);
779 
780 	return ret;
781 }
782 
783 /*
784  * Free the nandsim structure.
785  */
ns_free(struct nandsim * ns)786 static void ns_free(struct nandsim *ns)
787 {
788 	int i;
789 
790 	for (i = 0; i < ARRAY_SIZE(ns->partitions); ++i)
791 		kfree(ns->partitions[i].name);
792 
793 	kfree(ns->buf.byte);
794 	ns_free_device(ns);
795 
796 	return;
797 }
798 
ns_parse_badblocks(struct nandsim * ns,struct mtd_info * mtd)799 static int ns_parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
800 {
801 	char *w;
802 	int zero_ok;
803 	unsigned int erase_block_no;
804 	loff_t offset;
805 
806 	if (!badblocks)
807 		return 0;
808 	w = badblocks;
809 	do {
810 		zero_ok = (*w == '0' ? 1 : 0);
811 		erase_block_no = simple_strtoul(w, &w, 0);
812 		if (!zero_ok && !erase_block_no) {
813 			NS_ERR("invalid badblocks.\n");
814 			return -EINVAL;
815 		}
816 		offset = (loff_t)erase_block_no * ns->geom.secsz;
817 		if (mtd_block_markbad(mtd, offset)) {
818 			NS_ERR("invalid badblocks.\n");
819 			return -EINVAL;
820 		}
821 		if (*w == ',')
822 			w += 1;
823 	} while (*w);
824 	return 0;
825 }
826 
ns_parse_weakblocks(void)827 static int ns_parse_weakblocks(void)
828 {
829 	char *w;
830 	int zero_ok;
831 	unsigned int erase_block_no;
832 	unsigned int max_erases;
833 	struct weak_block *wb;
834 
835 	if (!weakblocks)
836 		return 0;
837 	w = weakblocks;
838 	do {
839 		zero_ok = (*w == '0' ? 1 : 0);
840 		erase_block_no = simple_strtoul(w, &w, 0);
841 		if (!zero_ok && !erase_block_no) {
842 			NS_ERR("invalid weakblocks.\n");
843 			return -EINVAL;
844 		}
845 		max_erases = 3;
846 		if (*w == ':') {
847 			w += 1;
848 			max_erases = simple_strtoul(w, &w, 0);
849 		}
850 		if (*w == ',')
851 			w += 1;
852 		wb = kzalloc(sizeof(*wb), GFP_KERNEL);
853 		if (!wb) {
854 			NS_ERR("unable to allocate memory.\n");
855 			return -ENOMEM;
856 		}
857 		wb->erase_block_no = erase_block_no;
858 		wb->max_erases = max_erases;
859 		list_add(&wb->list, &weak_blocks);
860 	} while (*w);
861 	return 0;
862 }
863 
ns_erase_error(unsigned int erase_block_no)864 static int ns_erase_error(unsigned int erase_block_no)
865 {
866 	struct weak_block *wb;
867 
868 	list_for_each_entry(wb, &weak_blocks, list)
869 		if (wb->erase_block_no == erase_block_no) {
870 			if (wb->erases_done >= wb->max_erases)
871 				return 1;
872 			wb->erases_done += 1;
873 			return 0;
874 		}
875 	return 0;
876 }
877 
ns_parse_weakpages(void)878 static int ns_parse_weakpages(void)
879 {
880 	char *w;
881 	int zero_ok;
882 	unsigned int page_no;
883 	unsigned int max_writes;
884 	struct weak_page *wp;
885 
886 	if (!weakpages)
887 		return 0;
888 	w = weakpages;
889 	do {
890 		zero_ok = (*w == '0' ? 1 : 0);
891 		page_no = simple_strtoul(w, &w, 0);
892 		if (!zero_ok && !page_no) {
893 			NS_ERR("invalid weakpages.\n");
894 			return -EINVAL;
895 		}
896 		max_writes = 3;
897 		if (*w == ':') {
898 			w += 1;
899 			max_writes = simple_strtoul(w, &w, 0);
900 		}
901 		if (*w == ',')
902 			w += 1;
903 		wp = kzalloc(sizeof(*wp), GFP_KERNEL);
904 		if (!wp) {
905 			NS_ERR("unable to allocate memory.\n");
906 			return -ENOMEM;
907 		}
908 		wp->page_no = page_no;
909 		wp->max_writes = max_writes;
910 		list_add(&wp->list, &weak_pages);
911 	} while (*w);
912 	return 0;
913 }
914 
ns_write_error(unsigned int page_no)915 static int ns_write_error(unsigned int page_no)
916 {
917 	struct weak_page *wp;
918 
919 	list_for_each_entry(wp, &weak_pages, list)
920 		if (wp->page_no == page_no) {
921 			if (wp->writes_done >= wp->max_writes)
922 				return 1;
923 			wp->writes_done += 1;
924 			return 0;
925 		}
926 	return 0;
927 }
928 
ns_parse_gravepages(void)929 static int ns_parse_gravepages(void)
930 {
931 	char *g;
932 	int zero_ok;
933 	unsigned int page_no;
934 	unsigned int max_reads;
935 	struct grave_page *gp;
936 
937 	if (!gravepages)
938 		return 0;
939 	g = gravepages;
940 	do {
941 		zero_ok = (*g == '0' ? 1 : 0);
942 		page_no = simple_strtoul(g, &g, 0);
943 		if (!zero_ok && !page_no) {
944 			NS_ERR("invalid gravepagess.\n");
945 			return -EINVAL;
946 		}
947 		max_reads = 3;
948 		if (*g == ':') {
949 			g += 1;
950 			max_reads = simple_strtoul(g, &g, 0);
951 		}
952 		if (*g == ',')
953 			g += 1;
954 		gp = kzalloc(sizeof(*gp), GFP_KERNEL);
955 		if (!gp) {
956 			NS_ERR("unable to allocate memory.\n");
957 			return -ENOMEM;
958 		}
959 		gp->page_no = page_no;
960 		gp->max_reads = max_reads;
961 		list_add(&gp->list, &grave_pages);
962 	} while (*g);
963 	return 0;
964 }
965 
ns_read_error(unsigned int page_no)966 static int ns_read_error(unsigned int page_no)
967 {
968 	struct grave_page *gp;
969 
970 	list_for_each_entry(gp, &grave_pages, list)
971 		if (gp->page_no == page_no) {
972 			if (gp->reads_done >= gp->max_reads)
973 				return 1;
974 			gp->reads_done += 1;
975 			return 0;
976 		}
977 	return 0;
978 }
979 
ns_setup_wear_reporting(struct mtd_info * mtd)980 static int ns_setup_wear_reporting(struct mtd_info *mtd)
981 {
982 	size_t mem;
983 
984 	wear_eb_count = div_u64(mtd->size, mtd->erasesize);
985 	mem = wear_eb_count * sizeof(unsigned long);
986 	if (mem / sizeof(unsigned long) != wear_eb_count) {
987 		NS_ERR("Too many erase blocks for wear reporting\n");
988 		return -ENOMEM;
989 	}
990 	erase_block_wear = kzalloc(mem, GFP_KERNEL);
991 	if (!erase_block_wear) {
992 		NS_ERR("Too many erase blocks for wear reporting\n");
993 		return -ENOMEM;
994 	}
995 	return 0;
996 }
997 
ns_update_wear(unsigned int erase_block_no)998 static void ns_update_wear(unsigned int erase_block_no)
999 {
1000 	if (!erase_block_wear)
1001 		return;
1002 	total_wear += 1;
1003 	/*
1004 	 * TODO: Notify this through a debugfs entry,
1005 	 * instead of showing an error message.
1006 	 */
1007 	if (total_wear == 0)
1008 		NS_ERR("Erase counter total overflow\n");
1009 	erase_block_wear[erase_block_no] += 1;
1010 	if (erase_block_wear[erase_block_no] == 0)
1011 		NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1012 }
1013 
1014 /*
1015  * Returns the string representation of 'state' state.
1016  */
ns_get_state_name(uint32_t state)1017 static char *ns_get_state_name(uint32_t state)
1018 {
1019 	switch (NS_STATE(state)) {
1020 		case STATE_CMD_READ0:
1021 			return "STATE_CMD_READ0";
1022 		case STATE_CMD_READ1:
1023 			return "STATE_CMD_READ1";
1024 		case STATE_CMD_PAGEPROG:
1025 			return "STATE_CMD_PAGEPROG";
1026 		case STATE_CMD_READOOB:
1027 			return "STATE_CMD_READOOB";
1028 		case STATE_CMD_READSTART:
1029 			return "STATE_CMD_READSTART";
1030 		case STATE_CMD_ERASE1:
1031 			return "STATE_CMD_ERASE1";
1032 		case STATE_CMD_STATUS:
1033 			return "STATE_CMD_STATUS";
1034 		case STATE_CMD_SEQIN:
1035 			return "STATE_CMD_SEQIN";
1036 		case STATE_CMD_READID:
1037 			return "STATE_CMD_READID";
1038 		case STATE_CMD_ERASE2:
1039 			return "STATE_CMD_ERASE2";
1040 		case STATE_CMD_RESET:
1041 			return "STATE_CMD_RESET";
1042 		case STATE_CMD_RNDOUT:
1043 			return "STATE_CMD_RNDOUT";
1044 		case STATE_CMD_RNDOUTSTART:
1045 			return "STATE_CMD_RNDOUTSTART";
1046 		case STATE_ADDR_PAGE:
1047 			return "STATE_ADDR_PAGE";
1048 		case STATE_ADDR_SEC:
1049 			return "STATE_ADDR_SEC";
1050 		case STATE_ADDR_ZERO:
1051 			return "STATE_ADDR_ZERO";
1052 		case STATE_ADDR_COLUMN:
1053 			return "STATE_ADDR_COLUMN";
1054 		case STATE_DATAIN:
1055 			return "STATE_DATAIN";
1056 		case STATE_DATAOUT:
1057 			return "STATE_DATAOUT";
1058 		case STATE_DATAOUT_ID:
1059 			return "STATE_DATAOUT_ID";
1060 		case STATE_DATAOUT_STATUS:
1061 			return "STATE_DATAOUT_STATUS";
1062 		case STATE_READY:
1063 			return "STATE_READY";
1064 		case STATE_UNKNOWN:
1065 			return "STATE_UNKNOWN";
1066 	}
1067 
1068 	NS_ERR("get_state_name: unknown state, BUG\n");
1069 	return NULL;
1070 }
1071 
1072 /*
1073  * Check if command is valid.
1074  *
1075  * RETURNS: 1 if wrong command, 0 if right.
1076  */
ns_check_command(int cmd)1077 static int ns_check_command(int cmd)
1078 {
1079 	switch (cmd) {
1080 
1081 	case NAND_CMD_READ0:
1082 	case NAND_CMD_READ1:
1083 	case NAND_CMD_READSTART:
1084 	case NAND_CMD_PAGEPROG:
1085 	case NAND_CMD_READOOB:
1086 	case NAND_CMD_ERASE1:
1087 	case NAND_CMD_STATUS:
1088 	case NAND_CMD_SEQIN:
1089 	case NAND_CMD_READID:
1090 	case NAND_CMD_ERASE2:
1091 	case NAND_CMD_RESET:
1092 	case NAND_CMD_RNDOUT:
1093 	case NAND_CMD_RNDOUTSTART:
1094 		return 0;
1095 
1096 	default:
1097 		return 1;
1098 	}
1099 }
1100 
1101 /*
1102  * Returns state after command is accepted by command number.
1103  */
ns_get_state_by_command(unsigned command)1104 static uint32_t ns_get_state_by_command(unsigned command)
1105 {
1106 	switch (command) {
1107 		case NAND_CMD_READ0:
1108 			return STATE_CMD_READ0;
1109 		case NAND_CMD_READ1:
1110 			return STATE_CMD_READ1;
1111 		case NAND_CMD_PAGEPROG:
1112 			return STATE_CMD_PAGEPROG;
1113 		case NAND_CMD_READSTART:
1114 			return STATE_CMD_READSTART;
1115 		case NAND_CMD_READOOB:
1116 			return STATE_CMD_READOOB;
1117 		case NAND_CMD_ERASE1:
1118 			return STATE_CMD_ERASE1;
1119 		case NAND_CMD_STATUS:
1120 			return STATE_CMD_STATUS;
1121 		case NAND_CMD_SEQIN:
1122 			return STATE_CMD_SEQIN;
1123 		case NAND_CMD_READID:
1124 			return STATE_CMD_READID;
1125 		case NAND_CMD_ERASE2:
1126 			return STATE_CMD_ERASE2;
1127 		case NAND_CMD_RESET:
1128 			return STATE_CMD_RESET;
1129 		case NAND_CMD_RNDOUT:
1130 			return STATE_CMD_RNDOUT;
1131 		case NAND_CMD_RNDOUTSTART:
1132 			return STATE_CMD_RNDOUTSTART;
1133 	}
1134 
1135 	NS_ERR("get_state_by_command: unknown command, BUG\n");
1136 	return 0;
1137 }
1138 
1139 /*
1140  * Move an address byte to the correspondent internal register.
1141  */
ns_accept_addr_byte(struct nandsim * ns,u_char bt)1142 static inline void ns_accept_addr_byte(struct nandsim *ns, u_char bt)
1143 {
1144 	uint byte = (uint)bt;
1145 
1146 	if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1147 		ns->regs.column |= (byte << 8 * ns->regs.count);
1148 	else {
1149 		ns->regs.row |= (byte << 8 * (ns->regs.count -
1150 						ns->geom.pgaddrbytes +
1151 						ns->geom.secaddrbytes));
1152 	}
1153 
1154 	return;
1155 }
1156 
1157 /*
1158  * Switch to STATE_READY state.
1159  */
ns_switch_to_ready_state(struct nandsim * ns,u_char status)1160 static inline void ns_switch_to_ready_state(struct nandsim *ns, u_char status)
1161 {
1162 	NS_DBG("switch_to_ready_state: switch to %s state\n",
1163 	       ns_get_state_name(STATE_READY));
1164 
1165 	ns->state       = STATE_READY;
1166 	ns->nxstate     = STATE_UNKNOWN;
1167 	ns->op          = NULL;
1168 	ns->npstates    = 0;
1169 	ns->stateidx    = 0;
1170 	ns->regs.num    = 0;
1171 	ns->regs.count  = 0;
1172 	ns->regs.off    = 0;
1173 	ns->regs.row    = 0;
1174 	ns->regs.column = 0;
1175 	ns->regs.status = status;
1176 }
1177 
1178 /*
1179  * If the operation isn't known yet, try to find it in the global array
1180  * of supported operations.
1181  *
1182  * Operation can be unknown because of the following.
1183  *   1. New command was accepted and this is the first call to find the
1184  *      correspondent states chain. In this case ns->npstates = 0;
1185  *   2. There are several operations which begin with the same command(s)
1186  *      (for example program from the second half and read from the
1187  *      second half operations both begin with the READ1 command). In this
1188  *      case the ns->pstates[] array contains previous states.
1189  *
1190  * Thus, the function tries to find operation containing the following
1191  * states (if the 'flag' parameter is 0):
1192  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1193  *
1194  * If (one and only one) matching operation is found, it is accepted (
1195  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1196  * zeroed).
1197  *
1198  * If there are several matches, the current state is pushed to the
1199  * ns->pstates.
1200  *
1201  * The operation can be unknown only while commands are input to the chip.
1202  * As soon as address command is accepted, the operation must be known.
1203  * In such situation the function is called with 'flag' != 0, and the
1204  * operation is searched using the following pattern:
1205  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1206  *
1207  * It is supposed that this pattern must either match one operation or
1208  * none. There can't be ambiguity in that case.
1209  *
1210  * If no matches found, the function does the following:
1211  *   1. if there are saved states present, try to ignore them and search
1212  *      again only using the last command. If nothing was found, switch
1213  *      to the STATE_READY state.
1214  *   2. if there are no saved states, switch to the STATE_READY state.
1215  *
1216  * RETURNS: -2 - no matched operations found.
1217  *          -1 - several matches.
1218  *           0 - operation is found.
1219  */
ns_find_operation(struct nandsim * ns,uint32_t flag)1220 static int ns_find_operation(struct nandsim *ns, uint32_t flag)
1221 {
1222 	int opsfound = 0;
1223 	int i, j, idx = 0;
1224 
1225 	for (i = 0; i < NS_OPER_NUM; i++) {
1226 
1227 		int found = 1;
1228 
1229 		if (!(ns->options & ops[i].reqopts))
1230 			/* Ignore operations we can't perform */
1231 			continue;
1232 
1233 		if (flag) {
1234 			if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1235 				continue;
1236 		} else {
1237 			if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1238 				continue;
1239 		}
1240 
1241 		for (j = 0; j < ns->npstates; j++)
1242 			if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1243 				&& (ns->options & ops[idx].reqopts)) {
1244 				found = 0;
1245 				break;
1246 			}
1247 
1248 		if (found) {
1249 			idx = i;
1250 			opsfound += 1;
1251 		}
1252 	}
1253 
1254 	if (opsfound == 1) {
1255 		/* Exact match */
1256 		ns->op = &ops[idx].states[0];
1257 		if (flag) {
1258 			/*
1259 			 * In this case the find_operation function was
1260 			 * called when address has just began input. But it isn't
1261 			 * yet fully input and the current state must
1262 			 * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1263 			 * state must be the next state (ns->nxstate).
1264 			 */
1265 			ns->stateidx = ns->npstates - 1;
1266 		} else {
1267 			ns->stateidx = ns->npstates;
1268 		}
1269 		ns->npstates = 0;
1270 		ns->state = ns->op[ns->stateidx];
1271 		ns->nxstate = ns->op[ns->stateidx + 1];
1272 		NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1273 		       idx, ns_get_state_name(ns->state),
1274 		       ns_get_state_name(ns->nxstate));
1275 		return 0;
1276 	}
1277 
1278 	if (opsfound == 0) {
1279 		/* Nothing was found. Try to ignore previous commands (if any) and search again */
1280 		if (ns->npstates != 0) {
1281 			NS_DBG("find_operation: no operation found, try again with state %s\n",
1282 			       ns_get_state_name(ns->state));
1283 			ns->npstates = 0;
1284 			return ns_find_operation(ns, 0);
1285 
1286 		}
1287 		NS_DBG("find_operation: no operations found\n");
1288 		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1289 		return -2;
1290 	}
1291 
1292 	if (flag) {
1293 		/* This shouldn't happen */
1294 		NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1295 		return -2;
1296 	}
1297 
1298 	NS_DBG("find_operation: there is still ambiguity\n");
1299 
1300 	ns->pstates[ns->npstates++] = ns->state;
1301 
1302 	return -1;
1303 }
1304 
ns_put_pages(struct nandsim * ns)1305 static void ns_put_pages(struct nandsim *ns)
1306 {
1307 	int i;
1308 
1309 	for (i = 0; i < ns->held_cnt; i++)
1310 		put_page(ns->held_pages[i]);
1311 }
1312 
1313 /* Get page cache pages in advance to provide NOFS memory allocation */
ns_get_pages(struct nandsim * ns,struct file * file,size_t count,loff_t pos)1314 static int ns_get_pages(struct nandsim *ns, struct file *file, size_t count,
1315 			loff_t pos)
1316 {
1317 	pgoff_t index, start_index, end_index;
1318 	struct page *page;
1319 	struct address_space *mapping = file->f_mapping;
1320 
1321 	start_index = pos >> PAGE_SHIFT;
1322 	end_index = (pos + count - 1) >> PAGE_SHIFT;
1323 	if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1324 		return -EINVAL;
1325 	ns->held_cnt = 0;
1326 	for (index = start_index; index <= end_index; index++) {
1327 		page = find_get_page(mapping, index);
1328 		if (page == NULL) {
1329 			page = find_or_create_page(mapping, index, GFP_NOFS);
1330 			if (page == NULL) {
1331 				write_inode_now(mapping->host, 1);
1332 				page = find_or_create_page(mapping, index, GFP_NOFS);
1333 			}
1334 			if (page == NULL) {
1335 				ns_put_pages(ns);
1336 				return -ENOMEM;
1337 			}
1338 			unlock_page(page);
1339 		}
1340 		ns->held_pages[ns->held_cnt++] = page;
1341 	}
1342 	return 0;
1343 }
1344 
ns_read_file(struct nandsim * ns,struct file * file,void * buf,size_t count,loff_t pos)1345 static ssize_t ns_read_file(struct nandsim *ns, struct file *file, void *buf,
1346 			    size_t count, loff_t pos)
1347 {
1348 	ssize_t tx;
1349 	int err;
1350 	unsigned int noreclaim_flag;
1351 
1352 	err = ns_get_pages(ns, file, count, pos);
1353 	if (err)
1354 		return err;
1355 	noreclaim_flag = memalloc_noreclaim_save();
1356 	tx = kernel_read(file, buf, count, &pos);
1357 	memalloc_noreclaim_restore(noreclaim_flag);
1358 	ns_put_pages(ns);
1359 	return tx;
1360 }
1361 
ns_write_file(struct nandsim * ns,struct file * file,void * buf,size_t count,loff_t pos)1362 static ssize_t ns_write_file(struct nandsim *ns, struct file *file, void *buf,
1363 			     size_t count, loff_t pos)
1364 {
1365 	ssize_t tx;
1366 	int err;
1367 	unsigned int noreclaim_flag;
1368 
1369 	err = ns_get_pages(ns, file, count, pos);
1370 	if (err)
1371 		return err;
1372 	noreclaim_flag = memalloc_noreclaim_save();
1373 	tx = kernel_write(file, buf, count, &pos);
1374 	memalloc_noreclaim_restore(noreclaim_flag);
1375 	ns_put_pages(ns);
1376 	return tx;
1377 }
1378 
1379 /*
1380  * Returns a pointer to the current page.
1381  */
NS_GET_PAGE(struct nandsim * ns)1382 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1383 {
1384 	return &(ns->pages[ns->regs.row]);
1385 }
1386 
1387 /*
1388  * Retuns a pointer to the current byte, within the current page.
1389  */
NS_PAGE_BYTE_OFF(struct nandsim * ns)1390 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1391 {
1392 	return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1393 }
1394 
ns_do_read_error(struct nandsim * ns,int num)1395 static int ns_do_read_error(struct nandsim *ns, int num)
1396 {
1397 	unsigned int page_no = ns->regs.row;
1398 
1399 	if (ns_read_error(page_no)) {
1400 		prandom_bytes(ns->buf.byte, num);
1401 		NS_WARN("simulating read error in page %u\n", page_no);
1402 		return 1;
1403 	}
1404 	return 0;
1405 }
1406 
ns_do_bit_flips(struct nandsim * ns,int num)1407 static void ns_do_bit_flips(struct nandsim *ns, int num)
1408 {
1409 	if (bitflips && prandom_u32() < (1 << 22)) {
1410 		int flips = 1;
1411 		if (bitflips > 1)
1412 			flips = (prandom_u32() % (int) bitflips) + 1;
1413 		while (flips--) {
1414 			int pos = prandom_u32() % (num * 8);
1415 			ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1416 			NS_WARN("read_page: flipping bit %d in page %d "
1417 				"reading from %d ecc: corrected=%u failed=%u\n",
1418 				pos, ns->regs.row, ns->regs.column + ns->regs.off,
1419 				nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1420 		}
1421 	}
1422 }
1423 
1424 /*
1425  * Fill the NAND buffer with data read from the specified page.
1426  */
ns_read_page(struct nandsim * ns,int num)1427 static void ns_read_page(struct nandsim *ns, int num)
1428 {
1429 	union ns_mem *mypage;
1430 
1431 	if (ns->cfile) {
1432 		if (!test_bit(ns->regs.row, ns->pages_written)) {
1433 			NS_DBG("read_page: page %d not written\n", ns->regs.row);
1434 			memset(ns->buf.byte, 0xFF, num);
1435 		} else {
1436 			loff_t pos;
1437 			ssize_t tx;
1438 
1439 			NS_DBG("read_page: page %d written, reading from %d\n",
1440 				ns->regs.row, ns->regs.column + ns->regs.off);
1441 			if (ns_do_read_error(ns, num))
1442 				return;
1443 			pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1444 			tx = ns_read_file(ns, ns->cfile, ns->buf.byte, num,
1445 					  pos);
1446 			if (tx != num) {
1447 				NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1448 				return;
1449 			}
1450 			ns_do_bit_flips(ns, num);
1451 		}
1452 		return;
1453 	}
1454 
1455 	mypage = NS_GET_PAGE(ns);
1456 	if (mypage->byte == NULL) {
1457 		NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1458 		memset(ns->buf.byte, 0xFF, num);
1459 	} else {
1460 		NS_DBG("read_page: page %d allocated, reading from %d\n",
1461 			ns->regs.row, ns->regs.column + ns->regs.off);
1462 		if (ns_do_read_error(ns, num))
1463 			return;
1464 		memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1465 		ns_do_bit_flips(ns, num);
1466 	}
1467 }
1468 
1469 /*
1470  * Erase all pages in the specified sector.
1471  */
ns_erase_sector(struct nandsim * ns)1472 static void ns_erase_sector(struct nandsim *ns)
1473 {
1474 	union ns_mem *mypage;
1475 	int i;
1476 
1477 	if (ns->cfile) {
1478 		for (i = 0; i < ns->geom.pgsec; i++)
1479 			if (__test_and_clear_bit(ns->regs.row + i,
1480 						 ns->pages_written)) {
1481 				NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1482 			}
1483 		return;
1484 	}
1485 
1486 	mypage = NS_GET_PAGE(ns);
1487 	for (i = 0; i < ns->geom.pgsec; i++) {
1488 		if (mypage->byte != NULL) {
1489 			NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1490 			kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1491 			mypage->byte = NULL;
1492 		}
1493 		mypage++;
1494 	}
1495 }
1496 
1497 /*
1498  * Program the specified page with the contents from the NAND buffer.
1499  */
ns_prog_page(struct nandsim * ns,int num)1500 static int ns_prog_page(struct nandsim *ns, int num)
1501 {
1502 	int i;
1503 	union ns_mem *mypage;
1504 	u_char *pg_off;
1505 
1506 	if (ns->cfile) {
1507 		loff_t off;
1508 		ssize_t tx;
1509 		int all;
1510 
1511 		NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1512 		pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1513 		off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1514 		if (!test_bit(ns->regs.row, ns->pages_written)) {
1515 			all = 1;
1516 			memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1517 		} else {
1518 			all = 0;
1519 			tx = ns_read_file(ns, ns->cfile, pg_off, num, off);
1520 			if (tx != num) {
1521 				NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1522 				return -1;
1523 			}
1524 		}
1525 		for (i = 0; i < num; i++)
1526 			pg_off[i] &= ns->buf.byte[i];
1527 		if (all) {
1528 			loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1529 			tx = ns_write_file(ns, ns->cfile, ns->file_buf,
1530 					   ns->geom.pgszoob, pos);
1531 			if (tx != ns->geom.pgszoob) {
1532 				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1533 				return -1;
1534 			}
1535 			__set_bit(ns->regs.row, ns->pages_written);
1536 		} else {
1537 			tx = ns_write_file(ns, ns->cfile, pg_off, num, off);
1538 			if (tx != num) {
1539 				NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1540 				return -1;
1541 			}
1542 		}
1543 		return 0;
1544 	}
1545 
1546 	mypage = NS_GET_PAGE(ns);
1547 	if (mypage->byte == NULL) {
1548 		NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1549 		/*
1550 		 * We allocate memory with GFP_NOFS because a flash FS may
1551 		 * utilize this. If it is holding an FS lock, then gets here,
1552 		 * then kernel memory alloc runs writeback which goes to the FS
1553 		 * again and deadlocks. This was seen in practice.
1554 		 */
1555 		mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1556 		if (mypage->byte == NULL) {
1557 			NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1558 			return -1;
1559 		}
1560 		memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1561 	}
1562 
1563 	pg_off = NS_PAGE_BYTE_OFF(ns);
1564 	for (i = 0; i < num; i++)
1565 		pg_off[i] &= ns->buf.byte[i];
1566 
1567 	return 0;
1568 }
1569 
1570 /*
1571  * If state has any action bit, perform this action.
1572  *
1573  * RETURNS: 0 if success, -1 if error.
1574  */
ns_do_state_action(struct nandsim * ns,uint32_t action)1575 static int ns_do_state_action(struct nandsim *ns, uint32_t action)
1576 {
1577 	int num;
1578 	int busdiv = ns->busw == 8 ? 1 : 2;
1579 	unsigned int erase_block_no, page_no;
1580 
1581 	action &= ACTION_MASK;
1582 
1583 	/* Check that page address input is correct */
1584 	if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1585 		NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1586 		return -1;
1587 	}
1588 
1589 	switch (action) {
1590 
1591 	case ACTION_CPY:
1592 		/*
1593 		 * Copy page data to the internal buffer.
1594 		 */
1595 
1596 		/* Column shouldn't be very large */
1597 		if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1598 			NS_ERR("do_state_action: column number is too large\n");
1599 			break;
1600 		}
1601 		num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1602 		ns_read_page(ns, num);
1603 
1604 		NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1605 			num, NS_RAW_OFFSET(ns) + ns->regs.off);
1606 
1607 		if (ns->regs.off == 0)
1608 			NS_LOG("read page %d\n", ns->regs.row);
1609 		else if (ns->regs.off < ns->geom.pgsz)
1610 			NS_LOG("read page %d (second half)\n", ns->regs.row);
1611 		else
1612 			NS_LOG("read OOB of page %d\n", ns->regs.row);
1613 
1614 		NS_UDELAY(access_delay);
1615 		NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1616 
1617 		break;
1618 
1619 	case ACTION_SECERASE:
1620 		/*
1621 		 * Erase sector.
1622 		 */
1623 
1624 		if (ns->lines.wp) {
1625 			NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1626 			return -1;
1627 		}
1628 
1629 		if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1630 			|| (ns->regs.row & ~(ns->geom.secsz - 1))) {
1631 			NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1632 			return -1;
1633 		}
1634 
1635 		ns->regs.row = (ns->regs.row <<
1636 				8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1637 		ns->regs.column = 0;
1638 
1639 		erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1640 
1641 		NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1642 				ns->regs.row, NS_RAW_OFFSET(ns));
1643 		NS_LOG("erase sector %u\n", erase_block_no);
1644 
1645 		ns_erase_sector(ns);
1646 
1647 		NS_MDELAY(erase_delay);
1648 
1649 		if (erase_block_wear)
1650 			ns_update_wear(erase_block_no);
1651 
1652 		if (ns_erase_error(erase_block_no)) {
1653 			NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1654 			return -1;
1655 		}
1656 
1657 		break;
1658 
1659 	case ACTION_PRGPAGE:
1660 		/*
1661 		 * Program page - move internal buffer data to the page.
1662 		 */
1663 
1664 		if (ns->lines.wp) {
1665 			NS_WARN("do_state_action: device is write-protected, programm\n");
1666 			return -1;
1667 		}
1668 
1669 		num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1670 		if (num != ns->regs.count) {
1671 			NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1672 					ns->regs.count, num);
1673 			return -1;
1674 		}
1675 
1676 		if (ns_prog_page(ns, num) == -1)
1677 			return -1;
1678 
1679 		page_no = ns->regs.row;
1680 
1681 		NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1682 			num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1683 		NS_LOG("programm page %d\n", ns->regs.row);
1684 
1685 		NS_UDELAY(programm_delay);
1686 		NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1687 
1688 		if (ns_write_error(page_no)) {
1689 			NS_WARN("simulating write failure in page %u\n", page_no);
1690 			return -1;
1691 		}
1692 
1693 		break;
1694 
1695 	case ACTION_ZEROOFF:
1696 		NS_DBG("do_state_action: set internal offset to 0\n");
1697 		ns->regs.off = 0;
1698 		break;
1699 
1700 	case ACTION_HALFOFF:
1701 		if (!(ns->options & OPT_PAGE512_8BIT)) {
1702 			NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1703 				"byte page size 8x chips\n");
1704 			return -1;
1705 		}
1706 		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1707 		ns->regs.off = ns->geom.pgsz/2;
1708 		break;
1709 
1710 	case ACTION_OOBOFF:
1711 		NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1712 		ns->regs.off = ns->geom.pgsz;
1713 		break;
1714 
1715 	default:
1716 		NS_DBG("do_state_action: BUG! unknown action\n");
1717 	}
1718 
1719 	return 0;
1720 }
1721 
1722 /*
1723  * Switch simulator's state.
1724  */
ns_switch_state(struct nandsim * ns)1725 static void ns_switch_state(struct nandsim *ns)
1726 {
1727 	if (ns->op) {
1728 		/*
1729 		 * The current operation have already been identified.
1730 		 * Just follow the states chain.
1731 		 */
1732 
1733 		ns->stateidx += 1;
1734 		ns->state = ns->nxstate;
1735 		ns->nxstate = ns->op[ns->stateidx + 1];
1736 
1737 		NS_DBG("switch_state: operation is known, switch to the next state, "
1738 			"state: %s, nxstate: %s\n",
1739 		       ns_get_state_name(ns->state),
1740 		       ns_get_state_name(ns->nxstate));
1741 
1742 		/* See, whether we need to do some action */
1743 		if ((ns->state & ACTION_MASK) &&
1744 		    ns_do_state_action(ns, ns->state) < 0) {
1745 			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1746 			return;
1747 		}
1748 
1749 	} else {
1750 		/*
1751 		 * We don't yet know which operation we perform.
1752 		 * Try to identify it.
1753 		 */
1754 
1755 		/*
1756 		 *  The only event causing the switch_state function to
1757 		 *  be called with yet unknown operation is new command.
1758 		 */
1759 		ns->state = ns_get_state_by_command(ns->regs.command);
1760 
1761 		NS_DBG("switch_state: operation is unknown, try to find it\n");
1762 
1763 		if (ns_find_operation(ns, 0))
1764 			return;
1765 
1766 		if ((ns->state & ACTION_MASK) &&
1767 		    ns_do_state_action(ns, ns->state) < 0) {
1768 			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1769 			return;
1770 		}
1771 	}
1772 
1773 	/* For 16x devices column means the page offset in words */
1774 	if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1775 		NS_DBG("switch_state: double the column number for 16x device\n");
1776 		ns->regs.column <<= 1;
1777 	}
1778 
1779 	if (NS_STATE(ns->nxstate) == STATE_READY) {
1780 		/*
1781 		 * The current state is the last. Return to STATE_READY
1782 		 */
1783 
1784 		u_char status = NS_STATUS_OK(ns);
1785 
1786 		/* In case of data states, see if all bytes were input/output */
1787 		if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1788 			&& ns->regs.count != ns->regs.num) {
1789 			NS_WARN("switch_state: not all bytes were processed, %d left\n",
1790 					ns->regs.num - ns->regs.count);
1791 			status = NS_STATUS_FAILED(ns);
1792 		}
1793 
1794 		NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1795 
1796 		ns_switch_to_ready_state(ns, status);
1797 
1798 		return;
1799 	} else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1800 		/*
1801 		 * If the next state is data input/output, switch to it now
1802 		 */
1803 
1804 		ns->state      = ns->nxstate;
1805 		ns->nxstate    = ns->op[++ns->stateidx + 1];
1806 		ns->regs.num   = ns->regs.count = 0;
1807 
1808 		NS_DBG("switch_state: the next state is data I/O, switch, "
1809 			"state: %s, nxstate: %s\n",
1810 		       ns_get_state_name(ns->state),
1811 		       ns_get_state_name(ns->nxstate));
1812 
1813 		/*
1814 		 * Set the internal register to the count of bytes which
1815 		 * are expected to be input or output
1816 		 */
1817 		switch (NS_STATE(ns->state)) {
1818 			case STATE_DATAIN:
1819 			case STATE_DATAOUT:
1820 				ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1821 				break;
1822 
1823 			case STATE_DATAOUT_ID:
1824 				ns->regs.num = ns->geom.idbytes;
1825 				break;
1826 
1827 			case STATE_DATAOUT_STATUS:
1828 				ns->regs.count = ns->regs.num = 0;
1829 				break;
1830 
1831 			default:
1832 				NS_ERR("switch_state: BUG! unknown data state\n");
1833 		}
1834 
1835 	} else if (ns->nxstate & STATE_ADDR_MASK) {
1836 		/*
1837 		 * If the next state is address input, set the internal
1838 		 * register to the number of expected address bytes
1839 		 */
1840 
1841 		ns->regs.count = 0;
1842 
1843 		switch (NS_STATE(ns->nxstate)) {
1844 			case STATE_ADDR_PAGE:
1845 				ns->regs.num = ns->geom.pgaddrbytes;
1846 
1847 				break;
1848 			case STATE_ADDR_SEC:
1849 				ns->regs.num = ns->geom.secaddrbytes;
1850 				break;
1851 
1852 			case STATE_ADDR_ZERO:
1853 				ns->regs.num = 1;
1854 				break;
1855 
1856 			case STATE_ADDR_COLUMN:
1857 				/* Column address is always 2 bytes */
1858 				ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1859 				break;
1860 
1861 			default:
1862 				NS_ERR("switch_state: BUG! unknown address state\n");
1863 		}
1864 	} else {
1865 		/*
1866 		 * Just reset internal counters.
1867 		 */
1868 
1869 		ns->regs.num = 0;
1870 		ns->regs.count = 0;
1871 	}
1872 }
1873 
ns_nand_read_byte(struct nand_chip * chip)1874 static u_char ns_nand_read_byte(struct nand_chip *chip)
1875 {
1876 	struct nandsim *ns = nand_get_controller_data(chip);
1877 	u_char outb = 0x00;
1878 
1879 	/* Sanity and correctness checks */
1880 	if (!ns->lines.ce) {
1881 		NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1882 		return outb;
1883 	}
1884 	if (ns->lines.ale || ns->lines.cle) {
1885 		NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1886 		return outb;
1887 	}
1888 	if (!(ns->state & STATE_DATAOUT_MASK)) {
1889 		NS_WARN("read_byte: unexpected data output cycle, state is %s return %#x\n",
1890 			ns_get_state_name(ns->state), (uint)outb);
1891 		return outb;
1892 	}
1893 
1894 	/* Status register may be read as many times as it is wanted */
1895 	if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1896 		NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1897 		return ns->regs.status;
1898 	}
1899 
1900 	/* Check if there is any data in the internal buffer which may be read */
1901 	if (ns->regs.count == ns->regs.num) {
1902 		NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1903 		return outb;
1904 	}
1905 
1906 	switch (NS_STATE(ns->state)) {
1907 		case STATE_DATAOUT:
1908 			if (ns->busw == 8) {
1909 				outb = ns->buf.byte[ns->regs.count];
1910 				ns->regs.count += 1;
1911 			} else {
1912 				outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1913 				ns->regs.count += 2;
1914 			}
1915 			break;
1916 		case STATE_DATAOUT_ID:
1917 			NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1918 			outb = ns->ids[ns->regs.count];
1919 			ns->regs.count += 1;
1920 			break;
1921 		default:
1922 			BUG();
1923 	}
1924 
1925 	if (ns->regs.count == ns->regs.num) {
1926 		NS_DBG("read_byte: all bytes were read\n");
1927 
1928 		if (NS_STATE(ns->nxstate) == STATE_READY)
1929 			ns_switch_state(ns);
1930 	}
1931 
1932 	return outb;
1933 }
1934 
ns_nand_write_byte(struct nand_chip * chip,u_char byte)1935 static void ns_nand_write_byte(struct nand_chip *chip, u_char byte)
1936 {
1937 	struct nandsim *ns = nand_get_controller_data(chip);
1938 
1939 	/* Sanity and correctness checks */
1940 	if (!ns->lines.ce) {
1941 		NS_ERR("write_byte: chip is disabled, ignore write\n");
1942 		return;
1943 	}
1944 	if (ns->lines.ale && ns->lines.cle) {
1945 		NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1946 		return;
1947 	}
1948 
1949 	if (ns->lines.cle == 1) {
1950 		/*
1951 		 * The byte written is a command.
1952 		 */
1953 
1954 		if (byte == NAND_CMD_RESET) {
1955 			NS_LOG("reset chip\n");
1956 			ns_switch_to_ready_state(ns, NS_STATUS_OK(ns));
1957 			return;
1958 		}
1959 
1960 		/* Check that the command byte is correct */
1961 		if (ns_check_command(byte)) {
1962 			NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1963 			return;
1964 		}
1965 
1966 		if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1967 			|| NS_STATE(ns->state) == STATE_DATAOUT) {
1968 			int row = ns->regs.row;
1969 
1970 			ns_switch_state(ns);
1971 			if (byte == NAND_CMD_RNDOUT)
1972 				ns->regs.row = row;
1973 		}
1974 
1975 		/* Check if chip is expecting command */
1976 		if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
1977 			/* Do not warn if only 2 id bytes are read */
1978 			if (!(ns->regs.command == NAND_CMD_READID &&
1979 			    NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
1980 				/*
1981 				 * We are in situation when something else (not command)
1982 				 * was expected but command was input. In this case ignore
1983 				 * previous command(s)/state(s) and accept the last one.
1984 				 */
1985 				NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, ignore previous states\n",
1986 					(uint)byte,
1987 					ns_get_state_name(ns->nxstate));
1988 			}
1989 			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1990 		}
1991 
1992 		NS_DBG("command byte corresponding to %s state accepted\n",
1993 			ns_get_state_name(ns_get_state_by_command(byte)));
1994 		ns->regs.command = byte;
1995 		ns_switch_state(ns);
1996 
1997 	} else if (ns->lines.ale == 1) {
1998 		/*
1999 		 * The byte written is an address.
2000 		 */
2001 
2002 		if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
2003 
2004 			NS_DBG("write_byte: operation isn't known yet, identify it\n");
2005 
2006 			if (ns_find_operation(ns, 1) < 0)
2007 				return;
2008 
2009 			if ((ns->state & ACTION_MASK) &&
2010 			    ns_do_state_action(ns, ns->state) < 0) {
2011 				ns_switch_to_ready_state(ns,
2012 							 NS_STATUS_FAILED(ns));
2013 				return;
2014 			}
2015 
2016 			ns->regs.count = 0;
2017 			switch (NS_STATE(ns->nxstate)) {
2018 				case STATE_ADDR_PAGE:
2019 					ns->regs.num = ns->geom.pgaddrbytes;
2020 					break;
2021 				case STATE_ADDR_SEC:
2022 					ns->regs.num = ns->geom.secaddrbytes;
2023 					break;
2024 				case STATE_ADDR_ZERO:
2025 					ns->regs.num = 1;
2026 					break;
2027 				default:
2028 					BUG();
2029 			}
2030 		}
2031 
2032 		/* Check that chip is expecting address */
2033 		if (!(ns->nxstate & STATE_ADDR_MASK)) {
2034 			NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, switch to STATE_READY\n",
2035 			       (uint)byte, ns_get_state_name(ns->nxstate));
2036 			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2037 			return;
2038 		}
2039 
2040 		/* Check if this is expected byte */
2041 		if (ns->regs.count == ns->regs.num) {
2042 			NS_ERR("write_byte: no more address bytes expected\n");
2043 			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2044 			return;
2045 		}
2046 
2047 		ns_accept_addr_byte(ns, byte);
2048 
2049 		ns->regs.count += 1;
2050 
2051 		NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2052 				(uint)byte, ns->regs.count, ns->regs.num);
2053 
2054 		if (ns->regs.count == ns->regs.num) {
2055 			NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2056 			ns_switch_state(ns);
2057 		}
2058 
2059 	} else {
2060 		/*
2061 		 * The byte written is an input data.
2062 		 */
2063 
2064 		/* Check that chip is expecting data input */
2065 		if (!(ns->state & STATE_DATAIN_MASK)) {
2066 			NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, switch to %s\n",
2067 			       (uint)byte, ns_get_state_name(ns->state),
2068 			       ns_get_state_name(STATE_READY));
2069 			ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2070 			return;
2071 		}
2072 
2073 		/* Check if this is expected byte */
2074 		if (ns->regs.count == ns->regs.num) {
2075 			NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2076 					ns->regs.num);
2077 			return;
2078 		}
2079 
2080 		if (ns->busw == 8) {
2081 			ns->buf.byte[ns->regs.count] = byte;
2082 			ns->regs.count += 1;
2083 		} else {
2084 			ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2085 			ns->regs.count += 2;
2086 		}
2087 	}
2088 
2089 	return;
2090 }
2091 
ns_nand_write_buf(struct nand_chip * chip,const u_char * buf,int len)2092 static void ns_nand_write_buf(struct nand_chip *chip, const u_char *buf,
2093 			      int len)
2094 {
2095 	struct nandsim *ns = nand_get_controller_data(chip);
2096 
2097 	/* Check that chip is expecting data input */
2098 	if (!(ns->state & STATE_DATAIN_MASK)) {
2099 		NS_ERR("write_buf: data input isn't expected, state is %s, switch to STATE_READY\n",
2100 		       ns_get_state_name(ns->state));
2101 		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2102 		return;
2103 	}
2104 
2105 	/* Check if these are expected bytes */
2106 	if (ns->regs.count + len > ns->regs.num) {
2107 		NS_ERR("write_buf: too many input bytes\n");
2108 		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2109 		return;
2110 	}
2111 
2112 	memcpy(ns->buf.byte + ns->regs.count, buf, len);
2113 	ns->regs.count += len;
2114 
2115 	if (ns->regs.count == ns->regs.num) {
2116 		NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2117 	}
2118 }
2119 
ns_nand_read_buf(struct nand_chip * chip,u_char * buf,int len)2120 static void ns_nand_read_buf(struct nand_chip *chip, u_char *buf, int len)
2121 {
2122 	struct nandsim *ns = nand_get_controller_data(chip);
2123 
2124 	/* Sanity and correctness checks */
2125 	if (!ns->lines.ce) {
2126 		NS_ERR("read_buf: chip is disabled\n");
2127 		return;
2128 	}
2129 	if (ns->lines.ale || ns->lines.cle) {
2130 		NS_ERR("read_buf: ALE or CLE pin is high\n");
2131 		return;
2132 	}
2133 	if (!(ns->state & STATE_DATAOUT_MASK)) {
2134 		NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2135 			ns_get_state_name(ns->state));
2136 		return;
2137 	}
2138 
2139 	if (NS_STATE(ns->state) != STATE_DATAOUT) {
2140 		int i;
2141 
2142 		for (i = 0; i < len; i++)
2143 			buf[i] = ns_nand_read_byte(chip);
2144 
2145 		return;
2146 	}
2147 
2148 	/* Check if these are expected bytes */
2149 	if (ns->regs.count + len > ns->regs.num) {
2150 		NS_ERR("read_buf: too many bytes to read\n");
2151 		ns_switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2152 		return;
2153 	}
2154 
2155 	memcpy(buf, ns->buf.byte + ns->regs.count, len);
2156 	ns->regs.count += len;
2157 
2158 	if (ns->regs.count == ns->regs.num) {
2159 		if (NS_STATE(ns->nxstate) == STATE_READY)
2160 			ns_switch_state(ns);
2161 	}
2162 
2163 	return;
2164 }
2165 
ns_exec_op(struct nand_chip * chip,const struct nand_operation * op,bool check_only)2166 static int ns_exec_op(struct nand_chip *chip, const struct nand_operation *op,
2167 		      bool check_only)
2168 {
2169 	int i;
2170 	unsigned int op_id;
2171 	const struct nand_op_instr *instr = NULL;
2172 	struct nandsim *ns = nand_get_controller_data(chip);
2173 
2174 	if (check_only)
2175 		return 0;
2176 
2177 	ns->lines.ce = 1;
2178 
2179 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
2180 		instr = &op->instrs[op_id];
2181 		ns->lines.cle = 0;
2182 		ns->lines.ale = 0;
2183 
2184 		switch (instr->type) {
2185 		case NAND_OP_CMD_INSTR:
2186 			ns->lines.cle = 1;
2187 			ns_nand_write_byte(chip, instr->ctx.cmd.opcode);
2188 			break;
2189 		case NAND_OP_ADDR_INSTR:
2190 			ns->lines.ale = 1;
2191 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
2192 				ns_nand_write_byte(chip, instr->ctx.addr.addrs[i]);
2193 			break;
2194 		case NAND_OP_DATA_IN_INSTR:
2195 			ns_nand_read_buf(chip, instr->ctx.data.buf.in, instr->ctx.data.len);
2196 			break;
2197 		case NAND_OP_DATA_OUT_INSTR:
2198 			ns_nand_write_buf(chip, instr->ctx.data.buf.out, instr->ctx.data.len);
2199 			break;
2200 		case NAND_OP_WAITRDY_INSTR:
2201 			/* we are always ready */
2202 			break;
2203 		}
2204 	}
2205 
2206 	return 0;
2207 }
2208 
ns_attach_chip(struct nand_chip * chip)2209 static int ns_attach_chip(struct nand_chip *chip)
2210 {
2211 	unsigned int eccsteps, eccbytes;
2212 
2213 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
2214 	chip->ecc.algo = bch ? NAND_ECC_ALGO_BCH : NAND_ECC_ALGO_HAMMING;
2215 
2216 	if (!bch)
2217 		return 0;
2218 
2219 	if (!IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_BCH)) {
2220 		NS_ERR("BCH ECC support is disabled\n");
2221 		return -EINVAL;
2222 	}
2223 
2224 	/* Use 512-byte ecc blocks */
2225 	eccsteps = nsmtd->writesize / 512;
2226 	eccbytes = ((bch * 13) + 7) / 8;
2227 
2228 	/* Do not bother supporting small page devices */
2229 	if (nsmtd->oobsize < 64 || !eccsteps) {
2230 		NS_ERR("BCH not available on small page devices\n");
2231 		return -EINVAL;
2232 	}
2233 
2234 	if (((eccbytes * eccsteps) + 2) > nsmtd->oobsize) {
2235 		NS_ERR("Invalid BCH value %u\n", bch);
2236 		return -EINVAL;
2237 	}
2238 
2239 	chip->ecc.size = 512;
2240 	chip->ecc.strength = bch;
2241 	chip->ecc.bytes = eccbytes;
2242 
2243 	NS_INFO("Using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2244 
2245 	return 0;
2246 }
2247 
2248 static const struct nand_controller_ops ns_controller_ops = {
2249 	.attach_chip = ns_attach_chip,
2250 	.exec_op = ns_exec_op,
2251 };
2252 
2253 /*
2254  * Module initialization function
2255  */
ns_init_module(void)2256 static int __init ns_init_module(void)
2257 {
2258 	struct list_head *pos, *n;
2259 	struct nand_chip *chip;
2260 	struct nandsim *ns;
2261 	int ret;
2262 
2263 	if (bus_width != 8 && bus_width != 16) {
2264 		NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2265 		return -EINVAL;
2266 	}
2267 
2268 	ns = kzalloc(sizeof(struct nandsim), GFP_KERNEL);
2269 	if (!ns) {
2270 		NS_ERR("unable to allocate core structures.\n");
2271 		return -ENOMEM;
2272 	}
2273 	chip	    = &ns->chip;
2274 	nsmtd       = nand_to_mtd(chip);
2275 	nand_set_controller_data(chip, (void *)ns);
2276 
2277 	/* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2278 	/* and 'badblocks' parameters to work */
2279 	chip->options   |= NAND_SKIP_BBTSCAN;
2280 
2281 	switch (bbt) {
2282 	case 2:
2283 		chip->bbt_options |= NAND_BBT_NO_OOB;
2284 		fallthrough;
2285 	case 1:
2286 		chip->bbt_options |= NAND_BBT_USE_FLASH;
2287 		fallthrough;
2288 	case 0:
2289 		break;
2290 	default:
2291 		NS_ERR("bbt has to be 0..2\n");
2292 		ret = -EINVAL;
2293 		goto free_ns_struct;
2294 	}
2295 	/*
2296 	 * Perform minimum nandsim structure initialization to handle
2297 	 * the initial ID read command correctly
2298 	 */
2299 	if (id_bytes[6] != 0xFF || id_bytes[7] != 0xFF)
2300 		ns->geom.idbytes = 8;
2301 	else if (id_bytes[4] != 0xFF || id_bytes[5] != 0xFF)
2302 		ns->geom.idbytes = 6;
2303 	else if (id_bytes[2] != 0xFF || id_bytes[3] != 0xFF)
2304 		ns->geom.idbytes = 4;
2305 	else
2306 		ns->geom.idbytes = 2;
2307 	ns->regs.status = NS_STATUS_OK(ns);
2308 	ns->nxstate = STATE_UNKNOWN;
2309 	ns->options |= OPT_PAGE512; /* temporary value */
2310 	memcpy(ns->ids, id_bytes, sizeof(ns->ids));
2311 	if (bus_width == 16) {
2312 		ns->busw = 16;
2313 		chip->options |= NAND_BUSWIDTH_16;
2314 	}
2315 
2316 	nsmtd->owner = THIS_MODULE;
2317 
2318 	ret = ns_parse_weakblocks();
2319 	if (ret)
2320 		goto free_ns_struct;
2321 
2322 	ret = ns_parse_weakpages();
2323 	if (ret)
2324 		goto free_wb_list;
2325 
2326 	ret = ns_parse_gravepages();
2327 	if (ret)
2328 		goto free_wp_list;
2329 
2330 	nand_controller_init(&ns->base);
2331 	ns->base.ops = &ns_controller_ops;
2332 	chip->controller = &ns->base;
2333 
2334 	ret = nand_scan(chip, 1);
2335 	if (ret) {
2336 		NS_ERR("Could not scan NAND Simulator device\n");
2337 		goto free_gp_list;
2338 	}
2339 
2340 	if (overridesize) {
2341 		uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2342 		struct nand_memory_organization *memorg;
2343 		u64 targetsize;
2344 
2345 		memorg = nanddev_get_memorg(&chip->base);
2346 
2347 		if (new_size >> overridesize != nsmtd->erasesize) {
2348 			NS_ERR("overridesize is too big\n");
2349 			ret = -EINVAL;
2350 			goto cleanup_nand;
2351 		}
2352 
2353 		/* N.B. This relies on nand_scan not doing anything with the size before we change it */
2354 		nsmtd->size = new_size;
2355 		memorg->eraseblocks_per_lun = 1 << overridesize;
2356 		targetsize = nanddev_target_size(&chip->base);
2357 		chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2358 		chip->pagemask = (targetsize >> chip->page_shift) - 1;
2359 	}
2360 
2361 	ret = ns_setup_wear_reporting(nsmtd);
2362 	if (ret)
2363 		goto cleanup_nand;
2364 
2365 	ret = ns_init(nsmtd);
2366 	if (ret)
2367 		goto free_ebw;
2368 
2369 	ret = nand_create_bbt(chip);
2370 	if (ret)
2371 		goto free_ns_object;
2372 
2373 	ret = ns_parse_badblocks(ns, nsmtd);
2374 	if (ret)
2375 		goto free_ns_object;
2376 
2377 	/* Register NAND partitions */
2378 	ret = mtd_device_register(nsmtd, &ns->partitions[0], ns->nbparts);
2379 	if (ret)
2380 		goto free_ns_object;
2381 
2382 	ret = ns_debugfs_create(ns);
2383 	if (ret)
2384 		goto unregister_mtd;
2385 
2386         return 0;
2387 
2388 unregister_mtd:
2389 	WARN_ON(mtd_device_unregister(nsmtd));
2390 free_ns_object:
2391 	ns_free(ns);
2392 free_ebw:
2393 	kfree(erase_block_wear);
2394 cleanup_nand:
2395 	nand_cleanup(chip);
2396 free_gp_list:
2397 	list_for_each_safe(pos, n, &grave_pages) {
2398 		list_del(pos);
2399 		kfree(list_entry(pos, struct grave_page, list));
2400 	}
2401 free_wp_list:
2402 	list_for_each_safe(pos, n, &weak_pages) {
2403 		list_del(pos);
2404 		kfree(list_entry(pos, struct weak_page, list));
2405 	}
2406 free_wb_list:
2407 	list_for_each_safe(pos, n, &weak_blocks) {
2408 		list_del(pos);
2409 		kfree(list_entry(pos, struct weak_block, list));
2410 	}
2411 free_ns_struct:
2412 	kfree(ns);
2413 
2414 	return ret;
2415 }
2416 
2417 module_init(ns_init_module);
2418 
2419 /*
2420  * Module clean-up function
2421  */
ns_cleanup_module(void)2422 static void __exit ns_cleanup_module(void)
2423 {
2424 	struct nand_chip *chip = mtd_to_nand(nsmtd);
2425 	struct nandsim *ns = nand_get_controller_data(chip);
2426 	struct list_head *pos, *n;
2427 
2428 	ns_debugfs_remove(ns);
2429 	WARN_ON(mtd_device_unregister(nsmtd));
2430 	ns_free(ns);
2431 	kfree(erase_block_wear);
2432 	nand_cleanup(chip);
2433 
2434 	list_for_each_safe(pos, n, &grave_pages) {
2435 		list_del(pos);
2436 		kfree(list_entry(pos, struct grave_page, list));
2437 	}
2438 
2439 	list_for_each_safe(pos, n, &weak_pages) {
2440 		list_del(pos);
2441 		kfree(list_entry(pos, struct weak_page, list));
2442 	}
2443 
2444 	list_for_each_safe(pos, n, &weak_blocks) {
2445 		list_del(pos);
2446 		kfree(list_entry(pos, struct weak_block, list));
2447 	}
2448 
2449 	kfree(ns);
2450 }
2451 
2452 module_exit(ns_cleanup_module);
2453 
2454 MODULE_LICENSE ("GPL");
2455 MODULE_AUTHOR ("Artem B. Bityuckiy");
2456 MODULE_DESCRIPTION ("The NAND flash simulator");
2457